ALBERT

Description: The British Isles lack long high-precision and independent chronologies to reconstruct Holocene environmental and climatic conditions at sub-decadal timescales. This paper reports the first Holocene varved chronology for the lacustrine sediment record of Diss Mere in the UK. The record of Diss Mere is 15 m long, and shows 4.2 m of finely-laminated sediments, which are present between ca. 9 and 13 m of core depth. The microfacies analysis identified three major seasonal patterns of deposition (microfacies 1–3), which corroborate the annual nature of sedimentation throughout the whole interval. The sediments are diatomaceous organic and carbonate varves with an average thickness of 0.45 mm. Microfacies 1 consists of a pale layer of authigenic calcite crystals and diatom frustules, and a dark layer composed of a planktonic diatoms and filaments of organic matter. Microfacies 2 is similar but includes a mono-specific diatom bloom layer preceding the calcite layer. Microfacies 3 consists of varves with an occasional very thin calcite layer and mono-specific diatom blooms in spring and autumn. A total of 8473 varves were counted with maximum counting error of up to 40 varves by the bottom of the varved sequence. To tie the resulting floating varve chronology to the IntCal 2020 radiocarbon timescale, we used a Bayesian Deposition model (P_Sequence with outlier detection) on all available chronological data from the core. The data included five radiocarbon dates, two known tephra layers (Glen Garry and OMH-185) with calendar ages based on Bayesian modelling of sequences of radiocarbon ages, and the relative varve counts between dated points. The resulting age-depth model (DISSV-2020) dates the varved sequence between ca. 2100 and 10,300 cal BP and age uncertainties are decadal in scale (95% confidence). The immediate implication of this new UK Holocene chronology is the updated precise ages for the Glen Garry tephra at 2073 ± 39 cal BP and the OMH-185 tephra at 2617 ± 29 cal BP. DISSV-2020 will also enable Holocene research at high time resolution and comparisons to other annually-resolved records on absolute timescales supporting climatic investigations at the regional level.

Description: This study of Lithium (Li) isotopes in surface waters and sediments in the catchment of Lake Bangong and the Upper Indus on the western Tibetan Plateau aims to identify processes that control Li isotope variations during weathering under a cold and hyper-arid climate. Additionally, Li isotope ratios in the Yarlung Tsangpo – Brahmaputra River were investigated. The lake and river sediments of Lake Bangong catchment display remarkable low δ7Li values between −4.7‰ and −0.6‰ relative to L-SVEC. Li isotopes in river bed sediments correlate with weathering intensity tracers such as the chemical index of alteration (CIA), K/(Na + K), or Na/Ti, and δ7Li values decrease continuously within the sediment cascade. These observations cannot be explained by mixing of different lithologies but reflects increasing intensity of weathering. The hyper-arid climate on the western plateau results in considerably long sediment residence times, which allows for overcoming the limitation of water availability on chemical weathering reactions. Samples from the Lake Bangong basins display low δ7Li values between +8.1‰ and +11.1‰. The major inflows have dissolved δ7Li values of +6.1‰ and +8.9‰. High Li/Na ratios in the stream waters indicate some contribution of hydrothermal Li. However, low δ7Li values in surface waters result from impeded silicate weathering processes in the thin soils. The samples from Indus headwaters and Yarlung Tsangpo provide evidence for low δ7Li all over the western and southern Tibetan Plateau. Using data of the Bangong Co, the Indus headwaters, and Yarlung Tsangpo, as well as published data from the northeastern plateau, we explore what controls Li isotope variation across the Tibetan plateau. Mass balance calculations suggest that similar proportions of dissolved Li and particulate Li are exported by river water and sediments on the western plateau. In contrast, high δ7Li values around +17‰ of the dissolved load in rivers on the northeastern Tibetan Plateau reflect a particulate Li export flux that is about five times higher than the export flux of dissolved Li. There is no first-order control by silicate weathering rates. The δ7Li differences largely follow the precipitation gradient across the Tibetan Plateau, which results in high net-incorporation of Li into clays on the northeastern but limits soil formation on the western Tibetan Plateau and, therefore limited, processing of lithium in the weathering zone.

Description: This data set is the part 8 of a series reporting chemical data for accessory minerals from felsic igneous rocks. Compositional data were acquired by electron-probe microanalysis (EPMA) between about 1995 and 2005 on surface rocks and borehole samples. This data set assembles the results of EPMA of fluorapatite from felsic rocks representing three groups of granites in the Erzgebirge−Vogtland metallogenic province of Germany emplaced in the late Carboniferous: F-poor biotite granites, F-poor two-mica granites, and P-F-rich Li-mica granite. In these rocks, fluorapatite is typically omnipresent. It has to be noted that apatite has not yet been in the focus of mineralogical studies of the granites in this province and a comprehensive survey of its compositional signature and variability in space and time is still pending. However, the data listed in this data set provide a valuable glimpse into the similarities and differences in apatite chemistry between geochemically distinct felsic rocks, and into the evolution in composition from early to late crystallizing apatite populations. The data underpin that apatite is a sensitive monitor of the compositional properties of the media (melts and fluids) from which it was deposited or with which it interacted. Apatite from the studied rocks is basically fluorapatite with little or no Cl and OH detected respectively inferred. Elemental variations are observed at various scales, i.e., between granite groups, subsequently crystallized sub-intrusion within composite massifs, grains present in a single thin section, or between the center and the rim of a particular grain. These variations in particular refer to the following elements: Mn, Fe, Na, and the rare-earth elements (REE). For example, measured Mn concentrations range from 0.15 to 8.8 wt% MnO. The data set contains the complete pile of electron-microprobe analyses for fluorapatite (APAT-ERZ-2020). The data are presented as Excel (xlsx) and tab-delimited text (txt) formats. The content of the tables and further information on the granites and regional geology are provided in the data description file.

Description: New apatite fission track (AFT) and (U–Th)/He (AHe) data from two sections recording Cretaceous-Cenozoic clastic successions (La Flecha - La Troya Sur creeks) in the northern sector of the Central Precordillera of Argentina are presented. The results show that the Ciénaga del Río Huaco, Puesto la Flecha and Vallecito Fms. would have crossed the 60 °C isotherm during burial, while the middle sector of the Vinchina Fm. would not have reached temperatures higher than 55 °C. Multimethod inverse thermal modeling suggests that the AFT ages of all the studied levels would not have been completely reset and allow inferring that the partial retention zone for the AHe system (AHe-PRZ) would have been reached during the Miocene in levels between the Vallecito and Vinchina Fms. Our 1D-modeling results for the Ciénaga del Río Huaco, Puesto la Flecha and Vallecito Fms. show that the maximum temperature would have been reached at ~15 Ma, with a sedimentary thickness of ~2750 m and a heat flow of 65 mW/m2. From these data, a geothermal gradient of ~27 °C/km at this time could be inferred. In turn, the Vinchina and Zapallar Fms. would have reached their maximum temperature at ~2 Ma, under a cooler thermal regime (20 mW/m2) and with an estimated geothermal gradient of 〈15 °C/km. Thus, a complex time-temperature trajectory is proposed. Maximum and cooling temperatures reached by each unit do not correspond in all cases to the maximum burial and exhumation times. Comparison of the thermal modelling from this work with those carried out by other authors for sections immediately to the north allows us to infer that the thermal regime within the Vinchina basin has important lateral variations. Finally, AFT and AHe analyzes carried out in this work constitute a baseline database of the thermal regime, which is necessary for future multiproxies studies that are being done to evaluate the preservation of primary thermal signals, and thus check their reliability for pealeoclimatic and paleoenvironmental interpretations.

Description: Soil Carbon (C) is central to the functioning of ecosystems and climate change mitigation. It represents the largest terrestrial pool and much of it, is stored in forest soils. Soil Organic Carbon (SOC) in a forest varies not only laterally, but also vertically (i.e., with depth). However, the SOC content of forest soil horizons has not been investigated over large scales, despite its importance for framing our understanding of soil function. Visible–Near Infrared (vis–NIR) reflectance spectroscopy enables rapid and cost-effective examination of forest SOC distribution, both laterally and vertically. This study aims to evaluate the potential of vis–NIR spectroscopy for classifying and predicting the SOC concentration of organic and mineral horizons in forests of the Czech Republic. We investigated 1080 forest sites across the country, each with five soil horizons, representing the Litter (L), Fragmented (F), and Humus (H) organic horizons, as well as the A1 (depth of 2–10 cm) and A2 (depth of 10–40 cm) mineral horizons. We, then, used Support Vector Machines (SVMs) to classify the soil horizons based on their spectra and also to model the SOC concentration of (i) the profile (organic and mineral horizons together), (ii) only the organic horizons, (iii) only the mineral horizons, and (iv) each individual horizon separately. The models were validated using 10-repeated 10-fold cross-validation. Results show that the SVM with radial basis kernel could accurately classify the soil horizons (Correct Classification Rate (CCR) of 70% and Kappa coefficient of 0.63). The SOC model developed for the soil profile performed well (R2 = 0.76 and RMSE = 1.63%). The model of the combined organic horizons was considerably more accurate than that of the combined mineral horizons (R2 = 0.78 and R2 = 0.53, respectively). Estimates of SOC in the individual soil horizons had R2 values greater than 0.63 but those of the F and A1 models were better with R2 〉 0.70. The study indicates that vis–NIR spectroscopy can effectively characterize the SOC concentration of the highly variable forest soil horizons in the Czech Republic.

Description: The International Geodynamics and Earth Tide Service (IGETS) was established in 2015 by the International Association of Geodesy (IAG). IGETS continues the activities of the Global Geodynamics Project (GGP, 1997-2015) to provide support to geodetic and geophysical research activities using superconducting gravimeter (SG) data within the context of an international network. The Membach station is located near the river Vesdre. It consists of a 130 m long gallery excavated in the side of the valley that rises to the Hautes Fagnes plateau. At the end of the gallery, there are two rooms, located at ~45 m below the ground surface. Room 1 is dedicated to absolute gravity and seismic measurements; room 2 houses the superconducting gravimeter. The structure of the gallery and the rooms is in reinforced concrete. It was built in the early 1970s to monitor the seismic activity in the vicinity of the Gileppe and Eupen water reservoirs. Works were performed contemporeanously with the raising of the Gileppe dam. The gallery has been excavated in low-porosity argillaceous sandstone with quartzitic beds. As a function of rainfall and seasonal effects, gravity variations up to 40 nms-2 have been observed, and are mostly due to groundwater changes in the vadose zone above the underground laboratory (Van Camp et al., 2006). Strong rainfall induces rapid gravity decreases (Meurers et al 2007; Delobbe et al., 2019). At the surface, a beech forest. Absolute gravity measurements have been performed on average every month since 1996, using the FG5#202 gravimeter and the station is also the reference point for the Belgian gravity network. The SG GWR#C021 has been operating continuously since 1995 August so that, since 2017 September 18, it holds both records for the longest continuous time spent measuring gravity variations in the same place and for the longest superconducting levitation of an artefact (Van Camp et al., 2017). For high precision works like Earth tides analysis on long time series, data should not be used before 1998 June 12, when the original "TIDE" card in the SG electronics was replaced by the "GGP" one. Filters are different, and so are the transfer functions. Moreover, in this early period, the SG suffered from numerous technical issues, causing several changes in the amplitude and phase calibrations and making it difficult to ensure that the data are as reliable as after 1998 June.

Description: This package provides a set of tools to read, manipulate and convert seismic waveforms generated by DAS systems. In particular, the ones saved in TDMs format: - dasconv: This utility lets you convert and manipulate seismic waveforms in TDMs format and export them into MiniSEED. - tdmsws (experimental) - a stand-alone implementation of the FDSN Dataselect web service, which is able to serve miniSEED data extracted from a folder with TDMS files.

Description: Are countries at a low level of socio-economic development catching up with developed countries over time or rather falling further behind? Existing work on the subject is not conclusive, partially due to methodological differences. The aim of the paper is to carry out a broader analysis with longer time series and a more diverse set of indicators. The study divides countries of the world into 21 developed “benchmark” countries and 156 developing countries. The distance between the benchmark and developing countries is measured using the “time lags” method, applied here to nine indicators covering topics such as the economy, health, education and the environment. The study further utilizes a probabilistic approach to extrapolate missing historical data for developing countries, so that the analysis can cover a full century starting in 1920 and ending with short-term projections to year 2020. The study finds that a majority of developing countries, and the population-weighted developing world as a whole, has reduced its lag in most indicators between 1920 and 2020. Progress was unevenly distributed, with East Asian and European countries converging the most with the benchmark, while most African countries have diverged along with some American ones. Catch-up in education attainment and life expectancy has been more successful than in infant survival rate, GDP per capita or technology adoption. The findings are put in context of United Nations’ Sustainable Development Goals, showing how the time lag method could improve setting targets for some of the goals. Further, time lags are used to analyze the current demographic, economic and political situation of developing countries, identifying opportunities and risks for future catch-up with developed countries.

Description: Artificial light at night (ALAN) can have negative impacts on the health of humans and ecosystems.1, 2, 3, 4 Marine organisms, including coral reefs in particular, rely on the natural light cycles of sunlight and moonlight to regulate various physiological, biological, and behavioral processes.5, 6, 7, 8 Here, we demonstrate that light pollution caused delayed gametogenesis and unsynchronized gamete release in two coral species, Acropora millepora and Acropora digitifera, from the Indo-Pacific Ocean. Given the urbanization along major coasts, light pollution could thus further threaten coral communities’ populations, which are already under severe degradation. A worldwide-modeled light pollution impact assessment is provided, which can help incorporate an important variable in coral reef conservation planning.

Description: The FOSA (FOgo Seismic Array) project has been carried out from October 2015 to December 2016 to investigate the seismicity of Fogo volcano after its eruption in 2014/2015. Fogo is the only volcano of the Cape Verde archipelago with reported historic eruptions. The eruptions occur frequently with an interval of about 20 years. However, the structure and extent of the related volcanic plumbing system are not well understood. The focus of the FOSA project was on the detection of ongoing magmatic activity and information about the plumbing system, using seismic array techniques. The array of the FOSA study was operated from October 2015 to December 2016, close to the village Achada Furna. From January 2016 we complemented the network with three additional broadband stations for an improved event detection and localization.

Description: This dataset comprises numerical outputs from the thermosphere-ionosphere-electrodynamics general circulation model (TIE-GCM) simulations described in the article "Modeling of planetary wave influences on the pre-reversal enhancement of the equatorial F region vertical plasma drift" (Yamazaki & Diéval, 2021).

Description: This dataset resulted from a parallel monitoring at two lakes, Lake Tiefer See (near Klocksin, TSK; 53° 35.5’ N, 12° 31.8’ E; 62 masl; N Germany) and Lake Czechowskie (Jezioro Czechowskie, JC; 53° 52.4’ N, 18° 14.3’ E; 108 masl; N Poland), and includes four different type of data for both locations: (i) sediment cores microfacies data, (ii) sediment fluxes and composition, (iii) selected water column data, and (iv) selected meteorological information obtained on site. This dual lake monitoring set-up was established in 2012 with the aim to investigate seasonal sedimentation and varve forming processes in detail. The datasets are provided in individual *.csv files, per type of data and per lake. The thin section data from surface sediment cores comprises the thicknesses of the most recent calcite varves’ sub-layers: spring diatom sub-layer, summer calcite sub-layer, and autumn/winter re-suspension sub-layer. The sediment flux data was obtained from sediment traps located in different water depths (epi- and hypolimnion), and the sediment composition is given by the fluxes of total organic carbon (TOC), calcium carbonate (as calculated from total inorganic carbon; TIC), and diatoms & inorganic matter. The water column data comprises water temperature from stationary loggers, and dissolved oxygen measured in ~ 1 meter depth-resolution. The meteorological data includes daily averages of air temperature and mean wind-speed, and summed daily rainfall. Further details about the sampling and analytical methods, data acquisition, and processing are given in Roeser et al. (2021; http://doi.org/10.1111/bor.12506).

Description: The cryosphere stands for environments where water appears in a frozen form. It includes permafrost, glaciers, ice sheets, and sea ice and is currently more affected by Global Change than most other regions of the Earth. In the cryosphere, limited water availability and subzero temperatures cause extreme conditions for all kind of life which microorganisms can cope with extremely well. The cryosphere’s microbiota displays an unexpectedly large genetic potential, and taxonomic as well as functional diversity which, however, we still only begin to map. Also, microbial communities influence reaction patterns of the cryosphere towards Global Change. Altered patterns of seasonal temperature fluctuations and precipitation are expected in the Arctic and will affect the microbial turnover of soil organic matter (SOM). Activation of nutrients by thawing and increased active layer thickness as well as erosion renders nutrient stocks accessible to microbial activities. Also, glacier melt and retreat stimulate microbial life in turn influencing albedo and surface temperatures. In this context, the functional resilience of microbial communities in the cryosphere is of major interest. Particularly important is the ability of microorganisms and microbial communities to respond to changes in their surroundings by intracellular regulation and population shifts within functional niches, respectively. Research on microbial life exposed to permanent freeze or seasonal freeze-thaw cycles has led to astonishing findings about microbial versatility, adaptation, and diversity. Microorganisms thrive in cold habitats and new sequencing techniques have produced large amounts of genomic, metagenomic, and metatranscriptomic data that allow insights into the fascinating microbial ecology and physiology at low and subzero temperatures. Moreover, some of the frozen ecosystems such as permafrost constitute major global carbon and nitrogen storages, but can also act as sources of the greenhouse gases methane and nitrous oxide. In this book we summarize state of the art knowledge on whether environmental changes are met by a flexible microbial community retaining its function, or if the altered conditions also render the community in a state of altered properties that affect the Earth’s element cycles and climate. This book brings together research on the cryosphere’s microbiota including permafrost, glaciers, and sea ice in Arctic and Antarctic regions. Different spatial scales and levels of complexity are considered, spanning from ecosystem level to pure culture studies of model microbes in the laboratory. It aims to attract a wide range of parties with interest in the effect of climate change and/or low temperatures on microbial nutrient cycling and physiology.

Description: The KISS network was installed in the frame of the “Klyuchevskoy Investigation - Seismic Structure of an extraordinary volcanic system” project and recorded data between summer 2015 and summer 2016 in one of the world’s largest clusters of subduction volcanoes - the Klyuchevskoy volcanic group (KVG). It is located in eastern Russia at the northern end of the Kuril-Kamchatka subduction zone close to its intersection with the Aleutian arc and the north-western termination of Hawaii-Emperor seamount chain. Additional to the 4700m high Mount Klyuchevskoy the KVG contains 12 other volcanoes that have together erupted about 1 cubic meter rock per second averaged over the past 10,000 years. Among those Klyuchevskoy, Bezymianny and Tolbachik were the most active ones during the last decades with eruptions styles ranging from explosive to Hawaiian-type. The KISS experiment is designed to investigate the volcanic and seismic processes and its structural setting in the KVG. The network covers a circular region of about 80km diameter with some linear extensions. It includes data from 77 temporary seismic stations with broadband and short period sensors that were installed on concrete plates in about 60cm deep holes. Due to the local conditions the stations were battery powered and could not be serviced during the experiment. GPS reception of the digitizers was not continuous at all stations due to thick snow cover and vegetation. Waveform data are available from the GEOFON data centre, under network code X9, and are embargoed until end of 2019.

Description: Die Industrialisierung der Nordhemisphäre führte zur Verschmutzung und Erwärmung natürlicher Ökosysteme. Bei vielen abgelegenen sibirischen Seen lassen sich weitgehende Folgen für ihre Rollen als Süßwasserressourcen und ökologische Refugien feststellen.

Description: Industrialisation in the Northern Hemisphere has led to the pollution and warming of natural ecosystems. Remote Siberian lakes are now under threat and face big environmental challenges that could have far-reaching consequences for freshwater resources and ecological refuges.

Description: Soil microorganisms globally are thought to be sustained primarily by organic carbon sources. Certain bacteria also consume inorganic energy sources such as trace gases, but they are presumed to be rare community members, except within some oligotrophic soils. Here we combined metagenomic, biogeochemical and modelling approaches to determine how soil microbial communities meet energy and carbon needs. Analysis of 40 metagenomes and 757 derived genomes indicated that over 70% of soil bacterial taxa encode enzymes to consume inorganic energy sources. Bacteria from 19 phyla encoded enzymes to use the trace gases hydrogen and carbon monoxide as supplemental electron donors for aerobic respiration. In addition, we identified a fourth phylum (Gemmatimonadota) potentially capable of aerobic methanotrophy. Consistent with the metagenomic profiling, communities within soil profiles from diverse habitats rapidly oxidized hydrogen, carbon monoxide and to a lesser extent methane below atmospheric concentrations. Thermodynamic modelling indicated that the power generated by oxidation of these three gases is sufficient to meet the maintenance needs of the bacterial cells capable of consuming them. Diverse bacteria also encode enzymes to use trace gases as electron donors to support carbon fixation. Altogether, these findings indicate that trace gas oxidation confers a major selective advantage in soil ecosystems, where availability of preferred organic substrates limits microbial growth. The observation that inorganic energy sources may sustain most soil bacteria also has broad implications for understanding atmospheric chemistry and microbial biodiversity in a changing world.

Description: Cerro Overo maar and La Albóndiga lava dome are two independent monogenetic volcanoes located in the Central Volcanic Zone of the Andes in northern Chile, close to the active Lascar and Chiliques volcanoes. Cerro Overo maar was formed 〈77 ka ago by explosive-effusive eruptions, including phreatomagmatic activity, while La Albóndiga lava dome (Pleistocene) is the result of magmatic explosive-effusive activity alone. Cerro Overo and La Albóndiga are characterized by deposits composed of pyroclastic rocks and dense coherent lava blocks. At Cerro Overo, these deposits are located around the crater rim, while at La Albóndiga, they form coherent in situ lava dome features. Cerro Overo also displays thin ash- and lapilli-dominated deposit layers presumed to be pyroclastic surge deposits, which include juvenile pyroclasts exhibiting cauliflower textures, numerous exotic accidental lithics, and ballistically transported lapilli, bombs, blocks, and bomb sags. These fragments include recycled, juvenile pyroclasts, as well as material from older volcanic and intrusive rocks from the stratigraphic units immediately below. These small-volume volcanoes represent two of the less silicic volcanoes (~54 wt.% SiO2) in the northern Chilean Pleistocene to Holocene volcanic provinces. They are characterized by a fine grain size (mainly fine lapilli), olivine phenocrysts with skeletal textures, ignimbritic, dioritic, and granitic xenoliths, and quartz xenocrysts, with high concentrations of incompatible trace elements and light rare earth elements. The general magmatic evolution of the Cerro Overo and La Albóndiga systems has been controlled by fast ascent (e.g., skeletal olivine phenocrysts) of mantle-derived magma associated with mixing, fractional crystallization, and a low degree of crustal assimilation during turbulent ascent processes. Such eruptions provide evidence that various factors play an essential role in the transition from explosive-effusive magmatic (Cerro Overo and La Albóndiga) to phreatomagmatic (Cerro Overo) volcanic eruption styles.

Description: The GRACE (Gravity Recovery and Climate Experiment) satellites, which comprises two spacecraft, GRACE-A and GRACE-B, were launched on 17 March 2002 into a near-circular, polar (inclination = 89◦ ) orbit with an initial altitude of about 490 km. The two satellites follow each other at a distance of about 200 km. The primary objective of the GRACE mission is to provide global high-resolution models of the Earth’s gravity field. The instruments supporting our study are the K-Band Ranging System (KBR), and the GPS Space Receiver (GPS). The K-Band Ranging System (KBR) system is the key science instrument of GRACE which measures the dual one-way range change between both satellites with a precision of about 1 μm per second. From the KBR1B data we can get the change of Total Electron Content (TEC). In addition the GPS Navigation Data (GNV1B) can provide us the position of the two satellites. From these data we can derive the average electron density between the two satellites. The data are stored as daily ASCII files using the file naming convention 'KBRNE_YYYY_MM_DD.dat'. Headers in each data file contain a short name for each column. A more detailed description is provided in the readme file.

Description: The software RST Evaluation is a series of scripts to semi-automatically evaluate shear experiments done at the Helmholtz Laboratory for Tectonic Modelling. In principle, it may be used for other measurements done in a similar setup, but it was build with our standardized workflow in mind. The shear experiments are done in a ring shear type shear cell rst.pc01 manufactured by D. Schulze (Details in ASTM standard D-6773). It uses an easy and reproducible workflow to determine yield properties, cohesion and dilational properties of a granular bulk material, such as sand or glass beads.

Description: This data is an high resolution Digital Elevation Model (DEM) generated for the Merapi summit by combining terrestrial laser scanning (TLS) and unmanned aerial vehicles (UAVs) photogrammetry data and TanDEM-X data acquired in the years between 2012 and 2017. The structures of the data are further analysed in Darmawan et al. 2017a (http://doi.org/10.1016/j.jvolgeores.2017.11.006), and a previous DEM was available in Darmawan et al. 2017b (https://doi.org/10.5880/GFZ.2.1.2017.003). The 3D point clouds of the different data were merged and interpolated to a raster format (Geotiff format).

Description: The Proterozoic Carpentaria province in northern Australia is host to several of the world’s largest clastic dominant (CD-type) massive sulphide deposits. These deposits are mostly hosted primarily in dolomitic silt- and mudstones. The hydrothermal alteration footprint of these CD-type systems is not well constrained, which poses challenges for the targeting of future discoveries. One important aspect to developing alteration models relates to defining the composition of the unaltered protolith to mineralization. In this dataset, we provide whole rock lithogeocheochemical data generated from samples obtained from drill-holes that intersected the mineralization in the Teena subbasin. A small number of samples are from 2 drill-holes from an adjoining subbasin (Myrtle) in the area. The samples were selected from stratigraphy of the Barney Creek Formation and are from the hangingwall to the mineralization in either subbasin. This data report includes bulk rock major, minor, and trace element composition. The data were generated using X-ray fluorescence, inductively coupled plasma mass spectrometry, and LECO analyses. Access to drill cores was granted by Teck Australia (Pty Ltd) and the drill core IDs and depths of individual samples are reported in the data table. For further details see: Magnall et al. (2021 - WHEN AVAILABLE)

Description: This dataset collects the results of a series of experiments carried out on air-filled cracks injected into pigskin gelatin blocks between September 2019 and May 2020 at GFZ German Research Centre for Geosciences in Potsdam (Germany). Such experiments were intended to simulate dike propagation in the upper crust, in settings where tectonic and surface unloading stress are dominant in determining the stress field within the medium. The gelatin blocks were laterally strained and rift-like excavations were moulded on their surfaces. These data include pictures of each experimental setup and video records of each injected crack, as well as tables collecting the measured arrival points of the cracks at the surface of the gelatin and relevant elastic and geometric parameters. The data publication is a Supplement to Mantiloni et al. (2020): "Stress inversion in a gelatin box: testing eruptive vent location forecasts with analog models" (Geophys. Res. Lett.), to which the reader is referred for further information.

Description: GFZ acts as a global analysis center of the International GNSS Service (IGS) and provides operationally ultra-rapid (last 24h), rapid (last day), and final (last week) solutions and contributes to the reprocessing activities of the IGS. The GFZ repro3 product solution series covers data from 1994 to 2020 and is published in daily and weekly files. The following satellite systems are contained: GPS (from 1994), GLONASS (from 2012), and Galileo (from 2014).

Description: Constraining Earth’s sediment mass balance over geologic time requires a quantitative understanding of how landscapes respond to transient tectonic perturbations. However, the mechanisms by which bedrock lithology governs landscape response remain poorly understood. Rock type influences the size of sediment delivered to river channels, which controls how efficiently rivers respond to tectonic forcing. The Mendocino triple junction region of northern California, USA, is one landscape in which large boulders, delivered by hillslope failures to channels, may alter the pace of landscape response to a pulse of rock uplift. Boulders frequently delivered by earthflows in one lithology, the Franciscan mélange, have been hypothesized to steepen channels and slow river response to rock uplift, helping to preserve high-elevation, low-relief topography. Channels in other units (the Coastal Belt and the Franciscan schist) may experience little or no erosion inhibition due to boulder delivery. Here we investigate spatial patterns in channel steepness, an indicator of erosion resistance, and how it varies between mélange and non-mélange channels. We then ask whether lithologically controlled boulder delivery to rivers is a possible cause of steepness variations. We find that mélange channels are steeper than Coastal Belt channels but not steeper than schist channels. Though channels in all units steepen with increasing proximity to mapped hillslope failures, absolute steepness values near failures are much higher (∼2×) in the mélange and schist than in Coastal Belt units. This could reflect reduced rock erodibility or increased erosion rates in the mélange and schist, or disproportionate steepening due to enhanced boulder delivery by hillslope failures in those units. To investigate the possible influence of lithology-dependent boulder delivery, we map boulders at failure toes in the three units. We find that boulder size, frequency, and concentration are greatest in mélange channels and that Coastal Belt channels have the lowest concentrations. Using our field data to parameterize a mathematical model for channel slope response to boulder delivery, we find that the modeled influence of boulders in the mélange could be strong enough to account for some observed differences in channel steepness between lithologies. At the landscape scale, we lack the data to fully disentangle boulder-induced steepening from that due to spatially varying erosion rates and in situ rock erodibility. However, our boulder mapping and modeling results suggest that lithology-dependent boulder delivery to channels could retard landscape adjustment to tectonic forcing in the mélange and potentially also in the schist. Boulder delivery may modulate landscape response to tectonics and help preserve high-elevation, low-relief topography at the Mendocino triple junction and elsewhere.

Description: The ability to constrain the petrogenesis of multiple serpentine generations recorded at the microscale is crucial for estimating the extent and conditions of modern versus fossil serpentinisation in ophiolites. To address matrix bias effects during oxygen isotope analysis by SIMS, we present the first investigation analysing antigorite in the compositional range Mg# = 77.5–99.5 mole %, using a CAMECA IMS‐1280 secondary ion mass spectrometer. Spot‐to‐spot homogeneity is ≤ 0.5‰ (2s) for the new antigorite reference materials. The relative bias between antigorite reference materials with different Mg/Fe ratios is described by a second‐order polynomial, and a maximum difference in bias of ~ 1.8‰ was measured for Mg# ~ 78 to 100. We observed a bias up to ~ 1.0‰ between lizardite and antigorite attributed to their different crystal structures. Orientation effects up to ~ 1‰ were observed in chrysotile. The new analytical protocol allowed the identification of oxygen isotope zoning up to ~ 7‰ in serpentine minerals from two serpentinites recovered from an area of active serpentinisation in the Samail ophiolite. Thus, in situ analysis is capable of resolving isotopic heterogeneity that may directly reflect changes in the physical and chemical conditions of multiple serpentinisation events in the Samail ophiolite.

Description: Here we report on a set of six apatite reference materials (chlorapatites MGMH# 133648, TUBAF# 38 and fluorapatites MGMH# 128441A, TUBAF# 37, 40, 50) which we have characterised for their chlorine isotope ratios; these RMs span a range of Cl mass fractions within the apatite Ca10(PO4)6(F,Cl,OH)2 solid solution series. Numerous apatite specimens, obtained from mineralogical collections, were initially screened for 37Cl/35Cl homogeneity using SIMS followed by δ37Cl characterisation by gas source mass spectrometry using both dual‐inlet and continuous‐flow modes. We also report major and key trace element compositions as determined by EPMA. The repeatability of our SIMS results was better than ± 0.10‰ (1s) for the five samples with 〉 0.5% m/m Cl, and ± 0.19‰ (1s) for the low Cl abundance material (0.27% m/m). We also observed a small, but significant crystal orientation effect of 0.38‰ between the mean 37Cl/35Cl ratios measured on three oriented apatite fragments. Furthermore, the results of GS‐IRMS analyses show small but systematic offset of δ37ClSMOC values between the three laboratories. Nonetheless, all studied samples have comparable chlorine isotope compositions, with mean 103δ37ClSMOC values between +0.09 and +0.42 and in all cases with 1s ≤ ± 0.25.

Description: S=2 oxoiron(IV) species act as reactive intermediates in the catalytic cycle of nonheme iron oxygenases. The few available synthetic S=2 FeIV=O complexes known to date are often limited to trigonal bipyramidal and very rarely to octahedral geometries. Herein we describe the generation and characterization of an S=2 pseudotetrahedral FeIV=O complex 2 supported by the sterically demanding 1,4,7‐tri‐tert‐butyl‐1,4,7‐triazacyclononane ligand. Complex 2 is a very potent oxidant in hydrogen atom abstraction (HAA) reactions with large non‐classical deuterium kinetic isotope effects, suggesting hydrogen tunneling contributions. For sterically encumbered substrates, direct HAA is impeded and an alternative oxidative asynchronous proton‐coupled electron transfer mechanism prevails, which is unique within the nonheme oxoiron community. The high reactivity and the similar spectroscopic parameters make 2 one of the best electronic and functional models for a biological oxoiron(IV) intermediate of taurine dioxygenase (TauD‐J).

Description: The use of lake sedimentary DNA to track the long-term changes in both terrestrial and aquatic biota is a rapidly advancing field in paleoecological research. Although largely applied nowadays, knowledge gaps remain in this field and there is therefore still research to be conducted to ensure the reliability of the sedimentary DNA signal. Building on the most recent literature and seven original case studies, we synthesize the state-of-the-art analytical procedures for effective sampling, extraction, amplification, quantification and/or generation of DNA inventories from sedimentary ancient DNA (sedaDNA) via high-throughput sequencing technologies. We provide recommendations based on current knowledge and best practises.

Description: In the EU-funded project Global Gravity-based Groundwater Product (G3P), we strive to combine data on terrestrial water storage from satellite gravimetry by the GRACE and GRACE-FO missions with existing products on water storage compartments from the Copernicus portfolio to establish a new cross-cutting product on groundwater storage variations with global coverage on a monthly basis. While the focus of G3P lies on incorporating observation-based Copernicus products, some model data has to be added to fill spatial and temporal gaps. This especially applies to water storage variations in surface water bodies, i.e., lakes and rivers, where little observation-based data is available. Altimetry-based data bases such as HYSOPE and the MGB model are available for large surface water bodies. However, to account for smaller water bodies and rivers, and to have a basis for assessing uncertainties of the entire approach, the integration of well-established models is desirable. A model we deem fit to these ends is Lisflood, which underpins the Global Flood Awareness System (GloFAS) of the Copernicus Emergency Management Service, and for which a recent global re-calibration is available. In this study, we evaluate Lisflood’s capability of modeling surface water storage variations in comparison to the above-mentioned observational data sources as well as the WaterGAP Global Hydrology Model (WGHM). As the target output of G3P is a 0.5° grid with monthly resolution,Lisflood’s output data will undergo an upscaling and temporal aggregation procedure which will also be subject of this study.

Description: In this study, the performance of ensemble precipitation forecasts of three numerical weather prediction (NWP) models within the TIGGE database as well as the integrated multi-satellite retrievals for global precipitation measurement (GPM), namely IMERG-RT V05B, for precipitation estimates were evaluated in recent severe floods in Iran over the March–April 2019 period. The evaluations were conducted in two modes: spatial distribution of precipitation and the dichotomous evaluation in four precipitation thresholds (25, 50, 75, and 100 mm per day). The results showed that the United Kingdom Met Office (UKMO) model, in terms of spatial coverage and satellite estimates as well as the precipitation amount, were closer to the observations. Although, generally, the models captured the spatial distribution of heavy precipitation events, the hot spots were not located in the correct area. The National Centers for Environmental Forecast (NCEP) model performed well at low precipitation thresholds, while at high thresholds, its performance decreased significantly. On the contrary, the accuracy of IMERG improved when the precipitation threshold increased. The UKMO had better forecasts than the other models at the 100 mm/day precipitation threshold, whereas the Medium-Range Weather Forecasts (ECMWF) had acceptable forecasts in all thresholds and was able to forecast precipitation events with a lower false alarm ratio and better detection when compared to other models. Although, the models and IMERG product underestimated or overestimated the amount of precipitation, but they were able to detect most extreme precipitation events. Overall, the results of this study show the IMERG precipitation estimates and NWP ensemble forecasts performed well in the three major flood events in spring 2019 in Iran. Given wide spread damages caused by the floods, the necessity of establishing an efficient flood warning system using the best precipitation products is advised.

Description: This study has been run in the context of the European Union research project G3P (Global Gravitybased Groundwater Product) on developing Groundwater storage (GW) as a new product for the EU Copernicus Services. GW variations can be derived on a global scale by subtracting from total water storage (TWS) variations based on the GRACE/GRACE-FO satellite missions variations in other water storage compartments such as soil moisture, snow, surface water bodies, and glaciers. Due to the nature of data acquisition by GRACE and GRACE-FO, the data need filtering in order to reduce North-South-oriented striping errors. However, this also leads to a spatially smoothed TWS signal. For a consistent subtraction of all individual storage compartments from GRACE-based TWS, the individual data sets for all other hydrological compartments need to be filtered in a similar way as GRACE-based TWS. In order to test different filter methods, we used compartmental water storage data of the global hydrological model WGHM. The decorrelation filter known as DDK filter that is routinely used for GRACE and GRACE-FO data introduced striping artifacts in the smoothed model data. Thus, we can conclude that the DDK filter is not suitable for filtering water storage data sets that do not exhibit GRACE-like correlated error patterns. Alternatively, an isotropic Gaussian filter might be used. The best filter width of the Gaussian filter is determined by minimizing the differences between the empirical spatial correlation functions of each water storage and the spatial correlation function of GRACE-based TWS. We also analyzed time variations of correlation lengths such as seasonal effects. Finally, the selected filter widths are applied to each compartmental storage data set to remove them from TWS and to obtain the GW variations.

Description: The metastable paragenesis of corundum and quartz is rare in nature but common in laboratory experiments where according to thermodynamic predictions aluminum–silicate polymorphs should form. We demonstrate here that the existence of a hydrous, silicon-bearing, nanometer-thick layer (called “HSNL”) on the corundum surface can explain this metastability in experimental studies without invoking unspecific kinetic inhibition. We investigated experimentally formed corundum reaction products synthesized during hydrothermal and piston–cylinder experiments at 500–800 °C and 0.25–1.8 GPa and found that this HSNL formed inside and on the corundum crystals, thereby controlling the growth behavior of its host. The HSNL represents a substitution of Al with Si and H along the basal plane of corundum. Along the interface of corundum and quartz, the HSNL effectively isolates the bulk phases corundum and quartz from each other, thus apparently preventing their reaction to the stable aluminum silicate. High temperatures and prolonged experimental duration lead to recrystallization of corundum including the HSNL and to the formation of quartz + fluid inclusions inside the host crystal. This process reduces the phase boundary area between the bulk phases, thereby providing further opportunity to expand their coexistence. In addition to its small size, its transient nature makes it difficult to detect the HSNL in experiments and even more so in natural samples. Our findings emphasize the potential impact of nanometer-sized phases on geochemical reaction pathways and kinetics under metamorphic conditions in one of the most important chemical systems of the Earth’s crust.

Description: We estimate vertical rotation rates for 204 earthquakes that were induced by the 2018 stimulation of the Espoo/Helsinki geothermal reservoir from wavefield gradients across geophone arrays. The array-derived rotation rates from seismograms recorded at 6–9 km hypocentral distances vary between 10−9 and 10−7 rad s−1, indicating a comparable sensitivity to portable rotational instruments. Using co-located observations of translational and rotational motion, we estimate the local propagation direction and the apparent phase speed of SH waves, and compare these estimates with those obtained by S wave beamforming. Propagation directions generally align with the earthquake back azimuths, but both techniques show deviations indicative of heterogeneous seismic structure. The rotational method facilitates a station-by-station approach that resolves site specific variations that are controlled by the local geology. We measure apparent S wave speeds larger than 5 km s−1, consistent with steep incidence angles and high propagation velocities in the Fennoscandian Shield.

Description: This data set was taken within the Perturbations of Earth Surface Processes by Large Earthquakes PRESSurE Project (https://www.gfz-potsdam.de/en/section/geomorphology/projects/pressure/) of the GFZ Potsdam. This project aims to better understand the role of earthquakes on earth surface processes. Strong earthquakes cause transient perturbations of the near Earth’s surface system. These include the widespread landsliding and subsequent mass movement and the loading of rivers with sediments. In addition, rock mass is shattered during the event, forming cracks that affect rock strength and hydrological conductivity. Often overlooked in the immediate aftermath of an earthquake, these perturbations can represent a major part of the overall disaster with an impact that can last for years before restoring to background conditions. Thus, the relaxation phase is part of the seismically induced change by an earthquake and needs to be monitored in order to understand the full impact of earthquakes on the Earth system. Early June 2015, shortly after the April 2015 Mw7.9 Gorkha earthquake, 6 automatic compact weather station were installed in the upper Bhotekoshi catchment covering an area ~50km2. The weather station network is centered around the Kahule Khola catchment, a small headwater catchment and is part of a wider data acquisition strategy including hydrological monitoring, seismometers, geophones and high resolution optical (RapidEye) as well as radar imagery (TanDEM TerraSAR-X). https://www.gfz-potsdam.de/sektion/geomorphologie/projekte/pressure/

Description: This data set was taken within the Perturbations of Earth Surface Processes by Large Earthquakes PRESSurE Project (https://www.gfz-potsdam.de/en/section/geomorphology/projects/pressure/) of the GFZ Potsdam. This project aims to better understand the role of earthquakes on earth surface processes. Strong earthquakes cause transient perturbations of the near Earth’s surface system. These include the widespread landsliding and subsequent mass movement and the loading of rivers with sediments. In addition, rock mass is shattered during the event, forming cracks that affect rock strength and hydrological conductivity. Often overlooked in the immediate aftermath of an earthquake, these perturbations can represent a major part of the overall disaster with an impact that can last for years before restoring to background conditions. Thus, the relaxation phase is part of the seismically induced change by an earthquake and needs to be monitored in order to understand the full impact of earthquakes on the Earth system. Early June 2015, shortly after the April 2015 Mw7.9 Gorkha earthquake, 6 automatic compact weather station were installed in the upper Bhotekoshi catchment covering an area ~50km2. The weather station network is centered around the Kahule Khola catchment, a small headwater catchment and is part of a wider data acquisition strategy including hydrological monitoring, seismometers, geophones and high resolution optical (RapidEye) as well as radar imagery (TanDEM TerraSAR-X). https://www.gfz-potsdam.de/sektion/geomorphologie/projekte/pressure/

Description: Minor release to include IGRF13 coefficients, expands the type of allowed inputs into the subsol routine, fixes several bugs in edge cases, expands testing support to include Python 3.6-3.9, updates the documentation, and updates the continuous integration testing environments.

Description: Microbial enhanced oil recovery (MEOR) is an economically attractive tertiary recovery technique and fermentative bacteria are frequently suggested for MEOR, partly because microbially produced organic acids have the potential for rock matrix dissolution. In this study, the metabolic activity and the community shift of a diverse microbiome of a high-salinity oilfield upon supplying MEOR nutrients was investigated in dynamic sandpacks set-up with and without crude oil using pure quartz sand and two types of reservoir rock. Geochemical characterization of the porous media included specific surface area (SSA), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). During the experiments, substrate and metabolites, incremental oil and differential pressure were monitored and the microbial community shift was investigated via Illumina sequencing. Fermentative Halanaerobiales outcompeted other microbes and led to an incremental oil recovery of 24.5 ± 9.6 %OOIP in reservoir rock. Microbial-induced dissolution of surface minerals was indicated by a decrease in SSA and surface-bound ferrous iron and concluded to be an important MEOR mechanism. Fermentation of sucrose was primarily limited by an insufficient acid neutralization capacity (ANC), but a carbonate content of 12% sustainably buffered the pH in a favorable growth range. Even minor amounts of other non-inert minerals (1% pyrite and calcite) facilitated microbial growth significantly, resulting in six-fold higher acetate production rates compared to quartz sand. Besides emphasizing the relevance of accessory minerals in MEOR, our results imply that the ANC could serve as potential screening parameter for predicting the performance of fermentation - based MEOR in the field.

Description: A common challenge for projects with multiple involved research institutes is a well-defined and productive collaboration. All parties measure and analyze different aspects, depend on each other, share common methods, and exchange the latest results, findings, and data. Today this exchange is often impeded by a lack of ready access to shared computing and storage resources. In our talk, we present a new and innovative remote procedure call (RPC) framework. We focus on a distributed setup, where project partners do not necessarily work at the same institute, and do not have access to each others resources. We present an application programming interface (API) developed in Python that enables scientists to collaboratively explore and analyze sets of distributed data. It offers the functionality to request remote data through a comfortable interface, and to share and invoke single computational methods or even entire analytical workflows and their results. The prototype enables researchers to make their methods accessible as a backend module running on their own infrastructure. Hence researchers from other institutes may apply the available methods through a lightweight python or Javascript API. In the end, the overhead for both, the backend developer and the remote user, is very low. The effort of implementing the necessary workflow and API usage equalizes the writing of code in a non-distributed setup. Besides that, data do not have to be downloaded locally, the analysis can be executed "close to the data" while using the institutional infrastructure where the eligible data set is stored. With our prototype, we demonstrate distributed data access and analysis workflows across institutional borders to enable effective scientific collaboration. This framework has been developed in a joint effort of the DataHub and Digitial Earth initiatives within the Research Centers of the Helmholtz Association of German Research Centres, HGF.

Description: The Tulaergen magmatic Ni–Cu deposit is related to mafic‐ultramafic rocks of the Central Asian Orogenic Belt. The ore‐host rocks are lherzolite and websterite and the major ore types are net‐textured and sparsely disseminated ores. The disseminated ores host high‐Fo (82–85) olivine and hornblende with low‐Al contents, high‐rare earth element (REE) abundances and negative Eu anomalies. The net‐textured mineralized lherzolite contains low‐Fo (74–82) olivine and high‐Al hornblende, the latter characterized by low REE concentrations and no Eu anomaly. The contrasting composition of olivine and hornblende suggests two stages of magmatism. In situ analysis of pentlandite, chalcopyrite and pyrrhotite shows that platinum‐group elements contents in sulphides are low. Contrasting Ni, Co, Se, Ag, Cd, and Pb contents in sulphides from net‐textured and in disseminated ores also supports two pulses of magmas, each with a distinct chemical composition. High‐Mg basaltic magma characterized the first stage, followed by a second‐stage less basic magma with a high H2O content. Whole‐rock Sr and Nd isotopic signatures suggest that about 4–6% crustal materials were added to the depleted mantle source. The fractional crystallization of olivine and crustal contamination play important roles in sulphur segregation at Tulaergen based on sulphur content at sulphide saturation modelling. Injection of magma enriched in H2O further enhanced sulphide aggregation and deposit forming. It is proposed that two pulses of magma injections occurred at the Tulaergen deposit, with the products of the first pulse settling at the base, and of the second one with dense mineralization laying at the top of the deposit.

Description: The data set contains VNIR and SWIR raw and reference hyperspectral imaging data of the Apliki mine open cut and of samples from the surface of the mine measured in the laboratory. It is con-nected to the published spectral library and chemical analyses of 37 different surface materials from the copper-gold-pyrite mine Apliki in the Republic of Cyprus (Koerting et al., 2019). The field outcrop scan was acquired in March 2018 in cooperation with the Geological Survey Department of the Republic of Cyprus (GSD) and the German Research Centre for Geosciences (GFZ). The laboratory sample scan presented in this document is a collection of hyperspectral scans compiled in one large dataset. The hyperspectral data in the field and the lab were acquired with the HySpex sys-tem in a range of 414 – 2498 nm. The field data is shared as one VNIR and one SWIR radiance and reflectance data cube each. The laboratory data is shared as one full VNIR-SWIR (414 – 2450nm) reflectance data cube that was processed and corrected for the detector jump, data spikes and the last 8 SWIR bands were clipped due to a low signal to noise ratio (SNR). The data and the samples originate from fieldwork in the Republic of Cyprus and laboratory work at the GFZ Potsdam. A detailed description of the data acquisition and processing can be found in Koerting (2021).

Description: Microbial mats, due to stratification of the redox zones, have a potential to include a complete N cycle, however an attempt to evaluate a complete N cycle in these ecosystems has not been yet made. In this study, occurrence and rates of major N cycle processes were evaluated in intact microbial mats from Elkhorn Slough, Monterey Bay, CA, USA, and Baja California Sur, Mexico under oxic and anoxic conditions using 15N-labeling techniques. All of the major N transformation pathways, with the exception of anammox, were detected in both microbial mats. Nitrification rates were found to be low at both sites for both seasons investigated. The highest rates of ammonium assimilation were measured in Elkhorn Slough mats in April and corresponded to high in situ ammonium concentration in the overlying water. Baja mats featured higher ammonification than ammonium assimilation rates and this, along with their higher affinity for nitrate compared to ammonium and low dissimilatory nitrate reduction to ammonium rates, characterized their differences from Elkhorn Slough mats. Nitrogen fixation rates in Elkhorn Slough microbial mats were found to be low implying that other processes such as recycling and assimilation from water are main sources of N for these mats at the times sampled. Denitrification in all of the mats was incomplete with nitrous oxide as end product and not dinitrogen. Our findings highlight N cycling features not previously quantified in microbial mats and indicate a need of further investigations in these microbial ecosystems.

Description: China has been said to have the largest putative shale gas resources in the world. The highest potential occurs in the Sichuan Basin, with the overmature Qiongzhusi (Cambrian) and Longmaxi (Silurian) Formations as prime exploration targets. Here the likelihood of late gas formation is examined using less mature equivalents from the Georgina Basin (Australia), and the Baltic Basin (Lithuania). We consider the respective roles played by kerogen and polar bitumen in gas generation with reference to the Eagle Ford, Yanchang, Niobrara, and Vaca Muerta Formations. Both of the lower Paleozoic shales are bitumen-poor in a geochemical sense, this being in stark contrast to the Mesozoic shales which are bitumen-rich. Kerogen is, therefore, the major gas precursor in the Cambrian and Silurian of the Sichuan Basin. Graptolites and solid bitumen are petrographically dominant. The solid bitumen exhibits flow structures and is deduced to be highly polar because it is insoluble in dichloromethane. Secondary cracking kinetics determined for the Arthur Creek using the GORfit Model are closely similar to source rocks containing predominantly paraffinic oil. Late gas generation from very stable refractory kerogen structures via alpha-cleavage reactions at maturities above 2% equivalent vitrinite reflectance was verified, and importantly, the upper ceiling for late gas generation in Paleozoic shales of the Sichuan Basin is set at 3% Ro. As far as the Qiongzhusi shale is concerned, raising the prospective acreage to a 3% Ro limit brings an additional contribution of 40 mg HC/g total organic carbon of late gas charge. The same is true for the extensive fairway of the Longmaxi shale along the western flank of the basin, close to the subcropping erosional edge.

Description: Background: Studies of the impact of environmental pollutants on health outcomes can be compromised by mismeasured exposures or unmeasured confounding with other environmental exposures. Both problems can be exacerbated by measuring exposure from data sources with low spatial resolution. Artificial light at night, for example, is often estimated from low-resolution satellite images, which may result in substantial measurement error and increased correlation with air or noise pollution. Methods: Light at night exposure was considered in simulated epidemiologic studies in Vancouver, British Columbia. First, we assessed statistical power and bias for hypothetical studies that replaced true light exposure with estimates from sources with low resolution. Next, health status was simulated based on pollutants other than light exposure, and we assessed the frequency with which studies might incorrectly attribute negative health impacts to light exposure as a result of unmeasured confounding by the other environmental exposures. Results: When light was simulated to be the causal agent, studies relying on low-resolution data suffered from lower statistical power and biased estimates. Additionally, correlations between light and other pollutants increased as the spatial resolution of the light exposure map decreased, so studies estimating light exposure from images with lower spatial resolution were more prone to confounding. Conclusions: Studies estimating exposure to pollutants from data with lower spatial resolution are prone to increased bias, increased confounding, and reduced power. Studies examining effects of light at night should avoid using exposure estimates based on low-resolution maps, and should consider potential confounding with other environmental pollutants. What this study adds

Description: Understanding the mechanical behaviors of granite after thermal treatment under loading and unloading conditions is of utmost relevance to deep geothermal energy recovery. In the present study, a series of loading and unloading triaxial compression tests (20, 40 and 60 MPa) on granite specimens after exposure to different temperatures (20, 200, 300, 400, 500 and 600 °C) was carried out to quantify the combined effects of thermal treatment and loading/unloading stress conditions on granite strength and deformation. Changes in the microstructure of granite exposed to high temperatures were revealed by optical microscopy. The experimental results indicate that both, thermal treatment and loading/unloading stress conditions, degrade the mechanical behaviors and further decrease the carrying capacity of granite. The gradual degradation of the mechanical characteristics of granite after thermal treatment is mainly associated with the evolution of thermal micro-cracks based on optical microscopy observations. The unloading stress state induces the extension of tension cracks parallel to the axial direction, and thus, the mechanical properties are degraded. Temperatures above 400 °C have a more significant influence on the mechanical characteristics of granite than the unloading treatment, whereby 400 °C can be treated as a threshold temperature for the delineation of significant deterioration. This study is expected to support feasibility and risk assessments by means of providing data for analytical calculations and numerical simulations on granite exposed to high temperatures during geothermal energy extraction.

Description: The oil expulsion efficiency of organic-rich shale during peak oil generation influences the generation of shale gas at high maturity, while the gas expulsion and loss efficiency affect the enrichment and preservation of shale gas. Two series of semiclosed hydrous pyrolysis experiments were performed under in situ geological conditions on Devonian shale sample as comparable analogue to evaluate the generation and preservation potential of shale gas in the Wufeng-Longmaxi Formation shale in the southeastern Sichuan Basin. The results indicate that the maximum oil expulsion efficiency of the Wufeng-Longmaxi shale is 68.8%. Retained oil is the main source of shale gas formed at high maturity. When the value of equal vitrinite reflectance (EqVRo) reaches 3.18%, the total gas generative potential from the retained oil and kerogen is 214.06 mL/g TOC, while that from kerogen is only 69.84 mL/g TOC. Overall, retained oil-formed gas at high maturity (EqVRo 〉1.30%) accounts for 60.82%–68.26% of the total gas, and the kerogen-formed gas is between 31.74% and 39.18% of the total gas. Based on the analysis of the JY2 well, Wufeng-Longmaxi shales with TOC contents 〉1.5% lose 60–80% of the total gas, while shales with TOC contents 〈1.5% lose 70–100% of the total gas. A TOC content of 1.5% can still meet the 2 m3/t gas content as evaluation standard for selecting favorable marine shale gas play areas in China.

Description: Soil erosion is generally recognized as the dominant process of land degradation. The formation and expansion of gullies is often a highly significant process of soil erosion. However, our ability to assess and simulate gully erosion and its impacts remains very limited. This is especially so at regional to continental scales. As a result, gullying is often overlooked in policies and land and catchment management strategies. Nevertheless, significant progress has been made over the past decades. Based on a review of 〉590 scientific articles and policy documents, we provide a state-of-the-art on our ability to monitor, model and manage gully erosion at regional to continental scales. In this review we discuss the relevance and need of assessing gully erosion at regional to continental scales (Section 1); current methods to monitor gully erosion as well as pitfalls and opportunities to apply them at larger scales (section 2); field-based gully erosion research conducted in Europe and European Russia (section 3); model approaches to simulate gully erosion and its contribution to catchment sediment yields at large scales (section 4); data products that can be used for such simulations (section 5); and currently existing policy tools and needs to address the problem of gully erosion (section 6). Section 7 formulates a series of recommendations for further research and policy development, based on this review. While several of these sections have a strong focus on Europe, most of our findings and recommendations are of global significance.

Description: A significant characteristic distinguishing Carlin-type Au deposits from other Au deposits is the abundance of invisible Au in arsenian pyrite. Gold occurs primarily as ionic Au1+ in arsenian pyrite and is unstable during subsequent thermal events. In this study, we used the focused ion beam combined with scanning electron microscope (FIB-SEM) techniques, and a transmission electron microscope (TEM) to examine invisible Au and how it evolved through later geologic events that eventually led to the formation of Au nanoparticles. FIB-SEM techniques were used to prepare site-specific TEM foils from four Carlin-type gold deposits, including Getchell and Cortez Hills, Nevada, USA, and Shuiyindong and Jinfeng, Guizhou Province, China. These samples were analyzed to quantify ore pyrite chemistry and evaluate textures at the nanometer scale. In 17 examined TEM foils, we observed widespread Au-rich domains in high-grade Au arsenian pyrites from the Getchell and Cortez Hills Au deposits and the Jinfeng deposit but only 10 Au-bearing nanoparticles, ~10 to 20 nm in diameter. The Au-rich domains exhibit Au (Sb), (Tl), (Hg), and (Cu) peaks in the energy dispersive X-ray (EDX) spectrum without the presence of recognizable nanoparticles. This confirms that Au is invisible even at a nanometer scale and is most likely present in the crystal structure of arsenian pyrite. Stacking faults and nanometer-sized fluid inclusions were commonly observed in Au-bearing arsenian pyrite from the four deposits, implying rapid crystallization. Moreover, unlike the coarsely crystalline arsenian pyrite from Guizhou Carlin-type Au deposits, arsenian pyrite from Carlin-type deposits in Nevada consists of fine-grained polycrystalline aggregates, further implying rapid crystallization. Additionally, curved dislocations were commonly pinned by solid inclusions, reflecting a former annealing process. Combining nanoscale textures with geologic information previously reported for Carlin-type deposits, invisible ionic Au was initially incorporated into the crystal structure of arsenian pyrite during rapid precipitation. Subsequent post-ore magmatic events in both districts initiated the annealing of the ionic Au-bearing arsenian pyrite, leading to the redistribution of trace elements and formation of Au-bearing nanoparticles in the arsenian pyrite. The presence of predominantly ionically bonded Au in arsenian pyrite confirms that ore fluids were not saturated in Au when Au-bearing arsenian pyrite formed, as previously reported for Carlin-type deposits. Ionic Au that was scavenged from an undersaturated ore fluid and incorporated into the arsenian pyrite crystal structure formed the giant Carlin-type Au deposits.

Description: GRACE-FO carries a magnetometer as part of its attitude orbit control system (AOCS). The magnetometer does not belong to the scientific payload of the mission. However, after postprocessing of the data, information on the geomagnetic field and on electric currents in near Earth space are derived. Each GRACE-FO satellite (GF1 and GF2) carries two fluxgate magnetometers (FGM), an active one, FGM A, and a redundant one, FGM B. So far, the redundant magnetometers were not switched and are not included in the data set. The provided data consists of raw magnetic field data as provided by L1b (RAW), Magnetic field data aligned, calibrated and corrected (ACAL_CORR), CHAOS7 magnetic model predictions for core, crustal and large-scale magnetospheric field (CHAOS7), Magnetic coordinates (APEX) and Radial and field-aligned currents derived from magnetic data in ACAL_CORR (FAC). The data are provided in NASA CDF format (https://cdf.gsfc.nasa.gov/).

Description: Field‐aligned currents play a major role in magnetized plasmas. They are the main agents for coupling the dynamics between magnetosphere and ionosphere. Perturbations of magnetic field distribution, plasma pressure or flow on one end are communicated by field‐aligned currents along the whole flux tube. Furthermore, they transport energy, practically lossless, from dynamo regions in the magnetosphere into the upper atmosphere. The knowledge of field‐aligned current distribution is therefore of great interest for understanding the magnetosphere‐ionosphere system. In this chapter we describe the expressions that illustrate the relationship between plasma motion in the magnetosphere and electric currents flowing along the background magnetic field. These currents can only be sensed above the ionospheric E‐layer, e.g. by low‐Earth orbiting satellites. However, to obtain reliable current density estimates is quite challenging. In a climatological sense, field‐aligned currents appear along two concentric rings in the high‐latitude ionosphere with opposite flow directions. Details of these patterns are controlled by the orientation of the interplanetary magnetic field. The transverse scale sizes determine important characteristics of field‐aligned currents.

Description: This report describes the KTB Borehole Measurements Data of the German Continental Deep Drilling Program (Kontinentales Tiefbohrprogramm der Bundesrepublik Deutschland), operated by the GFZ German Research Centre for Geosciences. Extensive borehole measurements were performed during the active drilling phase of the KTB pilot and main hole (1989-1994). This report provides the full description of the logging data. Please read it thoroughly to avoid inappropriate or wrong use of the data. The terms borehole measurements, downhole logging, and logging are used synonymously here. The KTB logging data files contain the final processed versions of the geoscientific borehole logging data from logs in the two KTB boreholes: Boreholes Geographic Coordinates (WGS84) KTB-Oberpfalz VB (KTB Vorbohrung/Pilot Hole or KTB-VB) 49.8153 N, 12.118 E KTB-Oberpfalz HB (KTB Hauptbohrung/Main Hole or KTB-HB) 49.8152 N, 12.1205 E

Description: Assessing the size of a former ocean of which only remnants are found in mountain belts is challenging but crucial to understanding subduction and exhumation processes. Here we present new constraints on the opening and width of the Piemont–Liguria (PL) Ocean, known as the Alpine Tethys together with the Valais Basin. We use a regional tectonic reconstruction of the Western Mediterranean–Alpine area, implemented into a global plate motion model with lithospheric deformation, and 2D thermo-mechanical modeling of the rifting phase to test our kinematic reconstructions for geodynamic consistency. Our model fits well with independent datasets (i.e., ages of syn-rift sediments, rift-related fault activity, and mafic rocks) and shows that, between Europe and northern Adria, the PL Basin opened in four stages: (1) rifting of the proximal continental margin in the Early Jurassic (200–180 Ma), (2) hyper-extension of the distal margin in the Early to Middle Jurassic (180–165 Ma), (3) ocean–continent transition (OCT) formation with mantle exhumation and MORB-type magmatism in the Middle–Late Jurassic (165–154 Ma), and (4) breakup and mature oceanic spreading mostly in the Late Jurassic (154–145 Ma). Spreading was slow to ultra-slow (max. 22 mm yr−1, full rate) and decreased to ∼5 mm yr−1 after 145 Ma while completely ceasing at about 130 Ma due to the motion of Iberia relative to Europe during the opening of the North Atlantic. The final width of the PL mature (“true”) oceanic crust reached a maximum of 250 km along a NW–SE transect between Europe and northwestern Adria. Plate convergence along that same transect has reached 680 km since 84 Ma (420 km between 84–35 Ma, 260 km between 35–0 Ma), which greatly exceeds the width of the ocean. We suggest that at least 63 % of the subducted and accreted material was highly thinned continental lithosphere and most of the Alpine Tethys units exhumed today derived from OCT zones. Our work highlights the significant proportion of distal rifted continental margins involved in subduction and exhumation processes and provides quantitative estimates for future geodynamic modeling and a better understanding of the Alpine Orogeny.

Description: The late-tectonic 511.4 ± 0.6 Ma-old Nomatsaus intrusion (Donkerhoek batholith, Damara orogen, Namibia) consists of moderately peraluminous, magnesian, calc-alkalic to calcic granites similar to I-type granites worldwide. Major and trace-element variations and LREE and HREE concentrations in evolved rocks imply that the fractionated mineral assemblage includes biotite, Fe–Ti oxides, zircon, plagioclase and monazite. Increasing K2O abundance with increasing SiO2 suggests accumulation of K-feldspar; compatible with a small positive Eu anomaly in the most evolved rocks. In comparison with experimental data, the Nomatsaus granite was likely generated from meta-igneous sources of possibly dacitic composition that melted under water-undersaturated conditions (X H2O: 0.25–0.50) and at temperatures between 800 and 850 °C, compatible with the zircon and monazite saturation temperatures of 812 and 852 °C, respectively. The Nomatsaus granite has moderately radiogenic initial 87Sr/86Sr ratios (0.7067–0.7082), relatively radiogenic initial εNd values (− 2.9 to − 4.8) and moderately evolved Pb isotope ratios. Although initial Sr and Nd isotopic compositions of the granite do not vary with SiO2 or MgO contents, fSm/Nd and initial εNd values are negatively correlated indicating limited assimilation of crustal components during monazite-dominated fractional crystallization. The preferred petrogenetic model for the generation of the Nomatsaus granite involves a continent–continent collisional setting with stacking of crustal slices that in combination with high radioactive heat production rates heated the thickened crust, leading to the medium-P/high-T environment characteristic of the southern Central Zone of the Damara orogen. Such a setting promoted partial melting of metasedimentary sources during the initial stages of crustal heating, followed by the partial melting of meta-igneous rocks at mid-crustal levels at higher P–T conditions and relatively late in the orogenic evolution.

Description: More and more studies worldwide show that seismic and aseismic slip can occur jointly, impacting the seismic hazard in a region. It is thus important to be able to reconstruct the deformation partitioning and fault interactions. In this study, we focus on the eastern Sea of Marmara region south of the megalopolis of Istanbul (Turkey). In this region, the plate-bounding North Anatolian Fault (NAF) is splitting into several branches. The northern branch is locked and is considered to host the nucleation zone of a M~7 earthquake expected for the region. In 2016, a 3-days long foreshock sequence preceded a MW 4.2 event located at the junction of the two or more sub-branches. It has been argued that this sequence may have been driven by aseismic slip involved in the earthquake nucleation (Malin et al., 2018). Starting around the time of this earthquake, a large strain signal, lasting 50 days, was identified on a single strainmeter station located ~30km from the M4.2 epicenter (Martinez-Garzon et al., 2019). To better characterize this sequence, we revisit it adding new types of data: we analyze GPS and InSAR data together with reprocessed strainmeter recordings of all the availaible stations in the region during 18 months framing the observed strain signal. To enhance the tectonic features in the strainmeter data, we apply a variational Bayesian Independent Component Analysis (vbICA, Gualandi et al. 2015). Following the M4.2 earthquake, we highlight a 50 km westward migration of the seismicity starting from its epicentral area and lasting 6 months. Increases in the seismic activity correspond to variations in the tectonic components of the recordings at two nearby strainmeters. The first changes in seismicity and strainmeter data occur 2.5 months before the MW4.2 event, and are also concomitant with a variation in the trend of the GPS data. The GPS data, along with the strainmeter ones, exhibit a second clear change at the time of the mainshock, that is also lasting two months. Similarly, the InSAR data highlight a variation in the time series around the time of the earthquake, lasting several weeks. The combination of these different types of measurements covering various signal-frequency bands of deformation in the eastern Sea of Marmara highlights the presence of a measurable large-scale and long-lasting deformation transient that begins and ends several weeks before and after the occurrence of a Mw4.2 earthquake. These observations show that further reducing the observational gap both in terms of detection threshold and frequency band allows to decipher signals that usually remain undetected. This is non-trivial but relevant for seismic hazard and risk assessment especially in case of submarine faults collocated with population centers, as is the case of the study region.

Description: Flood is one of the most widespread and frequent natural disasters. Deriving accurate and rapid cartographic information on flood extent is essential to help manage the situation. Satellite remote sensing is now widely used for near real-time flood monitoring as it provides large scale detection in a time- and cost-efficient manner. Optical satellite imagery is employed as important tools for flood mapping due to easier interpretability and high spatial resolution. However, cloudy weather associated with floods are a great obstacle to optical sensors for flood monitoring. In contrast, Synthetic Aperture Radar (SAR) allows observation of wide areas across near all-weather conditions and plays a significant role in operational services for flood management. Although in many cases smooth water surfaces can be easily extracted from SAR imagery, it is subjected to overestimation of flooded areas especially in the arid and semi-arid regions since the complex interactions between SAR characteristics and environmental conditions. Advanced machine learning and deep learning approaches have demonstrated large potential to overcome the problem by learning features directly from images which requires a large number of labeled samples for training and validation. Therefore, some public georeferenced dataset to train and test deep learning flood algorithms are being produced. To investigate the role of globally available label datasets in obtaining reliable flood maps using SAR data and deep learning approaches, we tried one of the open access dataset, Sen1Floods11, which is a surface water dataset. We trained, validated and tested a ResNet50 model to segment flood water using a subset of this dataset.The classification results of flood water have obtained an overall accuracy of 89.5% for the test dataset in India and 78.9% for the test dataset in Pakistan. Results show the potential of the flood water dataset to better detect the flooded area.

Description: The organic carbon-and uranium-rich, marine Alum Shale Formation in northwestern Europe (Middle Cambrian (Miaolingian) to Early Ordovician) was deposited in the Baltic Basin and surrounding areas. It is a proven source rock for conventional oil either in sandstones of Cambrian age or Ordovician and Silurian carbonates, and also contains a potential for shale oil and for biogenic or thermogenic shale gas. Despite the absence of higher land plant precursors, the primary Type II kerogen has an abnormally strong aromatic character at low thermal maturities due to α-particle bombardment by the elevated uranium content. The characteristic aromatic kerogen structure results in dead carbon formation and enhances hydrocarbon retention. As a consequence, effective petroleum expulsion is limited during maturation. The petroleum generation properties of the Alum Shale Formation changed over geological time due to the accumulated uranium irradiation. For thermally immature samples, high uranium content is positively correlated with high gas-oil ratios and the aromaticities of both the free hydrocarbons residing in the rock and the pyrolysis products from its kerogen. Such characteristics indicate that irradiation has had a strong influence on the overall organic matter composition and hence on the petroleum potential. At high uranium content, macromolecules are less alkylated than their less irradiated counterparts and oxygen containing-compounds are enriched. However, the kerogen structure was less altered during catagenesis (420–340 Ma bp) than at present, and thus calibration is needed to predict petroleum generation in time and space. In southern central Sweden biogenic methane in the Alum Shale Formation was formed during oil degradation after the Quaternary glaciation following bitumen impregnation generated from local magmatic Carboniferous – Permian intrusions. Consequently, the Alum Shale Formation includes a mixed shale oil/biogenic gas play that resembles the formation of biogenic methane in the Antrim Shale (Michigan Basin, United States). In the Alum Shale Formation, low salinity pore water created a subsurface aqueous environment, which was favourable for microbes that have the potential to form biogenic methane. The ability to generate biogenic methane from samples of the Alum Shale Formation in incubation experiments still exists today. The permeability coefficients of highly mature Alum Shale Formation from Bornholm Island (southern Baltic Sea) cover a broad range from sub-nanodarcy to microdarcy, depending on fluid type (i.e. gas vs. liquid), (in-situ) fluid content, anisotropy, pore pressure and effective stress conditions. In general, the primary high total organic carbon content was not significantly reduced at overmature stages, consistently with the high sorption capacities. The Alum Shale Formation is thus an attractive gas shale candidate from the perspective of gas generation and retention. The strength of the overmature Alum Shale Formation on Bornholm, which is mainly determined by mineral composition, porosity and spatial distribution of the constituents, is relatively low compared to other well-studied shale formations. Based on brittleness estimates, the Alum Shale Formation may be regarded as an unconventional reservoir rock of medium quality from the mechanical point of view.

Description: In situ sulfur (S) isotope ratios and trace element chemistry were simultaneously determined in a wide selection of different (natural) sulfides and sulfates using femtosecond laser ablation split stream (fsLASS) inductively coupled plasma mass spectrometry (ICP-MS). The laser aerosol is split between a sequential quadrupole ICP-MS for trace element quantification and a multi-collector ICP-MS (MC-ICP-MS) for stable sulfur isotope ratio measurements. This LASS method is able to simultaneously determine S isotope ratios and element chemistry without a compromise in the measurement precision and measurement accuracy of the S isotope ratios. The quantification of major and trace elements in sulfide minerals down to the μg g−1 level was achieved. LASS shows overall lower sensitivity and higher limits of detection in comparison to direct trace element determination using LA-ICP-MS only, due to the lower amounts of sample introduced into the ICP-qMS. This compromise is acceptable given the additional information gained from obtaining simultaneously both the isotopic and elemental compositions.

Description: Models of the glacial-isostatic adjustment (GIA) to past ice-mass changes exhibit large differences in north-east Greenland owing to insufficient knowledge about glacial history and Earth rheology. The GIA uncertainties feed back to uncertainties in present-day mass-balance estimates from satellite gravimetry. Geodetic Global Navigation Satellite System (GNSS) measurements allow to directly observe displacement of bedrock. We present results from repeated and continuous GNSS measurements conducted within five measurement campaigns between 2008 and 2017. We used the observed uplift rates to validate different GIA models in conjunction with estimates of the elastic response of the solid Earth to present-day ice-mass changes. To determine present-day ice-mass changes and the associated elastic deformations, we combined satellite altimetry data from CryoSat-2 with satellite gravimetry data from the Gravity Recovery and Climate Experiment for the entire Greenland Ice Sheet (GrIS) and included peripheral glaciers and ice caps. The different GIA models were consistently used in all processing steps. The GNSS measurements in north-east Greenland revealed uplift rates in the range of 2.8 to 8.9 mm yr−1. The comparison of the total displacement predicted by GIA and elastic modeling with the GNSS-based displacement clearly favors GIA models that show low rates (0.7–4.4 mm yr−1 at the GNSS sites) against GIA models with higher rates of up to 8.3 mm yr−1. The correction due to the favored GIA model in north-east Greenland results in an ice-mass loss of 233 ± 43 Gt yr−1 for the GrIS including peripheral glaciers over the period July 2010 to June 2017.

Description: Unconventional geothermal resource development can contribute to increase power generation from renewable energy sources in countries without conventional hydrothermal reservoirs, which are usually associated with magmatic activity and extensional faulting, as well as to expand the generation in those regions where conventional resources are already used. Three recent drilling experiences focused on the characterization of unconventional resources are described and compared: the Campi Flegrei Deep Drilling Project (CFDDP) in Italy, the United Downs Deep Geothermal Power (UDDGP) project in the United Kingdom, and the DEEP Earth Energy Production in Canada. The main aspects of each project are described (geology, drilling, data collection, communication strategies) and compared to discuss challenges encountered at the tree sites considered, including a scientific drilling project (CFDDP) and two industrial ones (UDDGP and DEEP). The first project, at the first stage of pilot hole, although not reaching deep supercritical targets, showed extremely high, very rare thermal gradients even at shallow depths. Although each project has its own history, as well as social and economic context, the lessons learned at each drilling site can be used to further facilitate geothermal energy development.

Description: The water cloud model (WCM) can be inverted to estimate leaf area index (LAI) using the intensity of backscatter from synthetic aperture radar (SAR) sensors. Published studies have demonstrated that the WCM can accurately estimate LAI if the model is effectively calibrated. However, calibration of this model requires access to field measures of LAI as well as soil moisture. In contrast, machine learning (ML) algorithms can be trained to estimate LAI from satellite data, even if field moisture measures are not available. In this study, a support vector machine (SVM) was trained to estimate the LAI for corn, soybeans, rice, and wheat crops. These results were compared to LAI estimates from the WCM. To complete this comparison, in situ and satellite data were collected from seven Joint Experiment for Crop Assessment and Monitoring (JECAM) sites located in Argentina, Canada, Germany, India, Poland, Ukraine and the United States of America (U.S.A.). The models used C-Band backscatter intensity for two polarizations (like-polarization (VV) and cross-polarization (VH)) acquired by the RADARSAT-2 and Sentinel-1 SAR satellites. Both the WCM and SVM models performed well in estimating the LAI of corn. For the SVM, the correlation (R) between estimated LAI for corn and LAI measured in situ was reported as 0.93, with a root mean square error (RMSE) of 0.64 m2m−2 and mean absolute error (MAE) of 0.51 m2m−2 . The WCM produced an R-value of 0.89, with only slightly higher errors (RMSE of 0.75 m2m−2 and MAE of 0.61 m2m−2 ) when estimating corn LAI. For rice, only the SVM model was tested, given the lack of soil moisture measures for this crop. In this case, both high correlations and low errors were observed in estimating the LAI of rice using SVM (R of 0.96, RMSE of 0.41 m2m−2 and MAE of 0.30 m2m−2 ). However, the results demonstrated that when the calibration points were limited (in this case for soybeans), the WCM outperformed the SVM model. This study demonstrates the importance of testing different modeling approaches over diverse agro-ecosystems to increase confidence in model performance.

Description: The high-precision X-ray diffraction setup for work with diamond anvil cells (DACs) in interaction chamber 2 (IC2) of the High Energy Density instrument of the European X-ray Free-Electron Laser is described. This includes beamline optics, sample positioning and detector systems located in the multipurpose vacuum chamber. Concepts for pump-probe X-ray diffraction experiments in the DAC are described and their implementation demonstrated during the First User Community Assisted Commissioning experiment. X-ray heating and diffraction of Bi under pressure, obtained using 20 fs X-ray pulses at 17.8 keV and 2.2 MHz repetition, is illustrated through splitting of diffraction peaks, and interpreted employing finite element modeling of the sample chamber in the DAC.

Description: TecVolSA (Tectonics and Volcanoes in South America) is a project dedicated to the development of an intelligent Earth Observation (EO) data exploitation system for monitoring various geophysical activities in South America. Three partners from the German Aerospace Center (DLR) and the German Research Centre for Geosciences (GFZ) are involved to combine their expertise in signal processing, geophysics and Artificial Intelligence (AI). The first milestone of the project is to perform interferometric processing on tens of terabytes of SAR data to generate deformation products. Efficient algorithms have been designed to accommodate big data processing. Employing these algorithms, five-year data archives of Sentinel-1 have been processed thus far. The data archives span an area of over 770,000 km² surrounding the central volcanic zone of the Andes. Products in the form of surface deformation velocity and displacement time series are generated as point-wise measurements. To ensure highly accurate deformation estimates, two novel techniques have been utilized: large-scale atmospheric correction and covariance-based phase estimation for distributed scatterers. The second milestone is automatic mining of the wealth of the deformation products to gain insights about anthropogenic and geophysical signals in the region. Here two challenges are faced: the variety of crustal deformation processes as well as the sheer volume of the data. A closer analysis of the estimated deformation velocity verifies the presence of various signals including tectonic movements, volcanic unrest and slope-induced deformations. Such variety requires the classification of the observed signals. Furthermore, the dataset includes displacement time series and velocity estimates of over 750 million data points. This data volume necessitates the incorporation of AI for efficient mining of the products. The aforementioned challenges are met by combining geophysical and signal processing expertise of the project partners, and translating them to the AI algorithms. The use of AI in EO is a growing topic with numerous successful applications. However, compared to the well-established AI applications of cartography and ground cover classification, there is not enough training data available for the analysis of tectonic and volcanic signals. Therefore, there is a need for synthetic data generation. GFZ produces geophysical models for the simulation of a diverse database that is used for the training of neural networks to autonomously discover significant events in deformation products. DLR employs supervised machine learning techniques based on simulated data to automatically detect volcanic deformation from InSAR products. Apart from this application, signals which are not attributed to volcanic deformation are automatically clustered for further studies by expert geologists. For this approach, we depend on InSAR and geometrical feature engineering as well as advanced unsupervised learning algorithms. In the presentation, examples of clustering similar points in terms of temporal progression and a prototype system for the automatic detection of volcanic deformations will be illustrated. Our system is being developed with scalability and transferability in mind. South America serves as a generic and challenging case for this development, as it reveals manifold geophysical and anthropogenic signals. Our ultimate goal is to apply the developed AI-assisted system for global processing.

Description: The Salt Range in Pakistan exposes Precambrian to Pleistocene strata outcropping along the Salt Range Thrust (SRT). To better understand the in‐situ Cambrian and Pliocene tectonic evolution of the Pakistan Subhimalaya, we have conducted low‐temperature thermochronological analysis using apatite (U‐Th‐Sm)/He and fission track dating. We combine cooling ages from different samples located along the thrust front of the SRT into a thermal model that shows two major cooling events associated with rifting and regional erosion in the Late Palaeozoic and SRT activity since the Pliocene. Our results suggest that the SRT maintained a long‐term average shortening rate of ~5–6 mm/yr and a high exhumation rate above the SRT ramp since ~4 Ma.

Description: In April 2019, large parts of Khuzestan province in Iran were affected by intense record rainfall in the Zagros mountains. Persian Gulf catchment received approximately 30% of its long-term average rainfall over the course of a few days. Karkheh and Dez, two of the major rivers in this catchment, overflowed their banks. As several dams, including Karkheh, with the country's largest capacity, reached their limits, the water had to be released from the reservoirs, which resulted in flooding downstream of the dams. Several cities and more than 200 villages were flooded, and many people had to be evacuated. Many of the dams affected by the 2019 flood were embankment dams, previously reported to exhibit post-construction settlements, at places reaching 13 cm/yr. Therefore, during and after the flood, significant concerns were raised about their health and stability. In this study, we use Sentinel-1 InSAR to monitor embankment dams' response in Khuzestan to the 2019 flood event. We process the full archive of Sentinel-1 using the Small Baseline Subset approach and estimate the time series of displacement for three different embankment dams in Khuzestan province. The first two studied dams are Karkheh and Gotvand, which have the country's largest capacities and became operational in 2001 and 2012, respectively. The third studied dam is the Masjed-Soleyman dam, previously reported to sustain a high displacement rate since its operation in 2002. The Sentinel-1 InSAR displacement results indicate that all observed dams exhibit long-term post-construction settlement before the flood, with rates varies from approximately 1 cm/yr for the Karkheh dam to 5 cm/yr for Gotvand dam and 8 cm/yr for Masjed-Soleyman dam. The time series of displacement for Karkheh and Gotvand dams show gentle changes of displacement in response to the increase in water level following the flood. However, for the Masjed-Soleyman dam, the movement accelerates sharply after the flood with more than 2 cm of displacement on the crest in only two months. For the Masjed-Soleyman dam experiencing the most severe effect of the flood, we also analyzed high-resolution data from TerraSAR-X and COSMO-SkyMed. The results provide a detailed picture of the displacement pattern over the crest and the dam's body before and after the flood.

Description: Over the years, various satellites like ERS-1, ERS-2 and Envisat has been in use for the interferometric capability for a wide range of geophysical and environmental applications. With the launches of Sentinel-1A and 1B satellites in 2014 and 2016 respectively, the availability of SAR data from every part of the world has been increased many folds. With short revisit times of 1-6 days, the Sentinel-1 and the planned Tandem-Land NISAR missions provide an unprecedented wealth of topography and surface change data using InSAR technique. Utilizing these Synthetic Aperture Radar (SAR) acquisitions, repeated approximately from the same point in space at different times, it is possible to produce measurements of ground deformations at some of the world’s active volcanoes and can be used to detect signs of volcanic unrest. Most of the existing traditional algorithms like Permanent Scatterer (PS) analysis and Small Baseline Subset (SBAS) technique are computationally extensive and cannot be applied in near real time to detect precursory deformation and transient deformations. To overcome this problem, we have adapted a minimum spanning tree (MST) based spatial independent component analysis (ICA) method to automatically detect deformation signals of volcanic unrest. We utilize the algorithm’s capability to isolate signals of geophysical interest from atmospheric artifacts, topography and other noise signals, before monitoring the evolution of these signals through time in order to detect the onset of a period of volcanic unrest, in near real time. We demonstrate our approach on synthetic datasets having different signal strengths, varying temporally. We also present the results of our approach on the volcanic unrest of Mt. Thorbjörn in Iceland on 2020 and also the volcanic unrest of a volcano in Mexico from 2017 to 2019.

Description: Experiments in laser-heated diamond anvil cells (LH DACs) are conducted to assess phase diagrams of planetary materials at high pressure-temperature (P-T) conditions; thus, reliable determination of temperature in LH DAC experiments is essential. Radiometric temperature determination in LH DACs relies on the assumption of sample's wavelength-independent optical properties (graybody assumption), which is not justified for major lower mantle materials. The result is that experimental phase diagrams contain systematic unconstrained errors. Here we estimate the systematic error in radiometric temperature of nongray polycrystalline bridgmanite (Bgm; Mg0.96Fe2+0.036Fe3+0.014Si0.99O3) in a LH DAC by modeling emission and absorption of thermal radiation in a sample with experimentally-constrained optical properties. A comparison to experimental data validates the models and reveals that thermal spectra measured in LH DAC experiments record the interaction of radiation with the hot nongray sample. The graybody assumption in the experiments on translucent Bgm (light extinction coefficient, k 〈 ∼250 cm-1 at 500–900 nm) yields temperatures ∼5% higher than the maximum temperature in the sample heated to ∼1900 K. In contrast, the graybody temperature of dark Bgm (k 〉 ∼1500 cm−1), such as that produced upon melt quenching in LH DACs, underestimates the maximum temperature by ∼10%. Our experimental results pose quantitative constraints on the effect of nongray optical properties on the uncertainty of radiometric temperature determination in Bgm in the LH DACs. Evaluating nongray temperature in the future would enable a revision of the Bgm to post-perovskite phase transition and the high-pressure melting curve of Bgm.

Description: This study focuses on seafloor methane seep sites and their distribution in the northwestern part of the German North Sea. Methane seepage is a common phenomenon along marine shelves and known to occur in the North Sea, but proof of their existence was lacking in the study area. Using a ship-based multibeam echosounder we detected a minimum of 166 flares that are indicative for free gas releases from the seafloor in the German “Entenschnabel” area, which are not related to morphologic expressions at the seafloor. However, a group of small depressions was detected lacking water column anomalies but with indications of dissolved fluid release. Spatial analysis revealed that flares were not randomly distributed but show a relation to locations of subsurface salt diapirs. More than 60% of all flares were found in the vicinity of the salt diapir “Berta”. Dissolved methane concentrations of ∼100 nM in bottom waters were ten times the background value in the “Entenschnabel” area (CH4 〈 10 nM), supporting the finding of enhanced seepage activity in this part of our study area. Furthermore, locations of flares were often related to acoustic blanking and high amplitude reflections in sediment profiler echograms, most prominently observed at location Berta. These hydroacoustic signatures are interpreted to result from increased free gas concentrations in the sediments. Electromagnetic seabed mapping depicts local sediment conductivity anomalies below a flare cluster at Berta, which can be explained by small amounts of free gas in the sediment. In our area of interest, ten abandoned well sites were included in our mapping campaign, but flare observations were spatially not related to these wells. Naturally seeping methane is presumably transported to the seafloor along sub-vertical faults, which have formed concurrently to the updoming salt. Due to the shallow water depths of 30 to 50 m in the study area, flares were observed to reach close to the sea surface and a slight oversaturation of surface waters with methane in the flare-rich northeastern part of the working area indicates that part of the released methane through seepage may contribute to the atmospheric inventory.

Description: The Arctic–boreal zone (ABZ) is experiencing amplified warming, actively changing biogeochemical cycling of vegetation and soils. The land-to-atmosphere fluxes of CO2 in the ABZ have the potential to increase in magnitude and feedback to the climate causing additional large-scale warming. The ability to model and predict this vulnerability is critical to preparation for a warming world, but Earth system models have biases that may hinder understanding of the rapidly changing ABZ carbon fluxes. Here we investigate circumpolar carbon cycling represented by the Community Land Model 5 (CLM5.0) with a focus on seasonal gross primary productivity (GPP) in plant functional types (PFTs). We benchmark model results using data from satellite remote sensing products and eddy covariance towers. We find consistent biases in CLM5.0 relative to observational constraints: (1) the onset of deciduous plant productivity to be late; (2) the offset of productivity to lag and remain abnormally high for all PFTs in fall; (3) a high bias of grass, shrub, and needleleaf evergreen tree productivity; and (4) an underestimation of productivity of deciduous trees. Based on these biases, we focus on model development of alternate phenology, photosynthesis schemes, and carbon allocation parameters at eddy covariance tower sites. Although our improvements are focused on productivity, our final model recommendation results in other component CO2 fluxes, e.g., net ecosystem exchange (NEE) and terrestrial ecosystem respiration (TER), that are more consistent with observations. Results suggest that algorithms developed for lower latitudes and more temperate environments can be inaccurate when extrapolated to the ABZ, and that many land surface models may not accurately represent carbon cycling and its recent rapid changes in high-latitude ecosystems, especially when analyzed by individual PFTs.

Description: A change from a humid to an arid climate occurred during the Middle Jurassic. Information about this transitional phase is stored in two oil shales: the lower and upper units of the shale member of the Shimengou Formation (J2s) in the northern Qaidam Basin (NQB), Northwest China. The drastic changes in lithofacies are also reflected in the organic and inorganic inventory of the two oil shales, and suggests the existence of this aridification event. Thus, the two units varied greatly in organic matter source, productivities and depositional environments. The lower unit is interpreted as lacustrine sediment deposited under a humid climate with a high terrigenous organic matter portion besides algal biomass. Furthermore, the high sedimentation rate and large organic matter size prevented organic matter degradation. In contrast, deposition of the upper unit was coincident with progressive aridification, which resulted in minor terrigenous organic matter input, and enhanced algal biomass deposition. Its preservation was favored by an enhanced salinity and stratification of water column with an underlying anoxic bottom water condition. Today, the sediments of the upper unit are characterized by a high total organic carbon (TOC) content and type I kerogen. In summary, two depositional scenarios of source rock formation under different climatic conditions are introduced to highlight the effect of progressive aridification on the evolution of source rocks. Moderate aridification in the transition period (early stage of aridification) is suggested to have promoted the formation of lacustrine source rocks with the potential to generate waxy oil. The occurrence of similar lacustrine source rocks is also predictable when deposited while similar aridification events, particularly in the Jurassic with its frequent climate changes.

Description: The Makran subduction zone has produced M 8+ earthquakes and subsequent tsunamis in historic times, hence indicating high risk for the coastal regions of southern Iran, Pakistan, and neighboring countries. Besides this, the Makran subduction zone is an end-member subduction zone featuring extreme properties, with one of the largest sediment inputs and the widest accretionary wedge on Earth. While surface geology and shallow structure of the offshore wedge have been relatively well studied, primary information on the deeper structure of the onshore part is largely absent. We present three crustal-scale, trench-perpendicular, deep seismic sounding profiles crossing the subaerial part of the accretionary wedge of the western Makran subduction zone in Iran. P-wave travel-time tomography based on a Monte Carlo Markov chain algorithm as well as the migration of automatic line drawings of wide-angle reflections reveal the crustal structure of the wedge and geometry of the subducting oceanic plate at high resolution. The images shed light on the accretionary processes, in particular the generation of continental crust by basal accretion, and provide vital basic information for hazard assessment and tsunami modeling

Description: Paleotemperature changes during the Late Quaternary are mainly derived from marine and ice core records. However, there are relatively few temperature reconstructions from the East Asian Monsoon region, which has hindered our mechanistic understanding so far. To address this issue, a new time series of paleo-temperature was developed, based on the analysis of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from the well-dated sedimentary record of Sihailongwan maar lake (Lake SHL). This was achieved in two steps. Firstly, the sources and timing of seasonal production of brGDGTs were evaluated in the modern settings of Lake SHL. Secondly, using this information, we attempted to correct the temperature bias from soil derived brGDGTs using a binary mixing model, and a quantitative reconstruction of the paleo-temperature was derived from the Lake SHL brGDGTs sequence for the period of ∼60-8 ka BP. The results show that brGDGTs in Lake SHL are produced predominantly in summer and autumn (June–November). The sediment record reveals several important points: 1) the summer-autumn temperatures over the period ∼60–8 ka BP varied between ∼7 °C and ∼12.5 °C and the coldest period occurred during ∼25-21 ka BP when the mean summer-autumn temperature was ∼8.2 °C, 2) the summer-autumn temperature in Northeast China began to increase at ∼21 ka BP, and gradually warmed until the early Holocene in agreement with what has been recorded in southern China, most likely forced by summer insolation at 65°N.

Description: Permafrost thaw leads to thermokarst lake formation and talik growth tens of meters deep, enabling microbial decomposition of formerly frozen organic matter (OM). We analyzed two 17‐m‐long thermokarst lake sediment cores taken in Central Yakutia, Russia. One core was from an Alas lake in a Holocene thermokarst basin that underwent multiple lake generations, and the second core from a young Yedoma upland lake (formed ~70 years ago) whose sediments have thawed for the first time since deposition. This comparison provides a glance into OM fate in thawing Yedoma deposits. We analyzed total organic carbon (TOC) and dissolved organic carbon (DOC) content, n‐alkane concentrations, and bacterial and archaeal membrane markers. Furthermore, we conducted 1‐year‐long incubations (4°C, dark) and measured anaerobic carbon dioxide (CO2) and methane (CH4) production. The sediments from both cores contained little TOC (0.7 ± 0.4 wt%), but DOC values were relatively high, with the highest values in the frozen Yedoma lake sediments (1620 mg L−1). Cumulative greenhouse gas (GHG) production after 1 year was highest in the Yedoma lake sediments (226 ± 212 µg CO2‐C g−1 dw, 28 ± 36 µg CH4‐C g−1 dw) and 3 and 1.5 times lower in the Alas lake sediments, respectively (75 ± 76 µg CO2‐C g−1 dw, 19 ± 29 µg CH4‐C g−1 dw). The highest CO2 production in the frozen Yedoma lake sediments likely results from decomposition of readily bioavailable OM, while highest CH4 production in the non‐frozen top sediments of this core suggests that methanogenic communities established upon thaw. The lower GHG production in the non‐frozen Alas lake sediments resulted from advanced OM decomposition during Holocene talik development. Furthermore, we found that drivers of CO2 and CH4 production differ following thaw. Our results suggest that GHG production from TOC‐poor mineral deposits, which are widespread throughout the Arctic, can be substantial. Therefore, our novel data are relevant for vast ice‐rich permafrost deposits vulnerable to thermokarst formation.

Description: The present study aimed to quantify the thermally induced deformation and the associated evolution of permeability in Blaubeuren limestone, an outcrop analogue of the Upper Jurassic (Malm) carbonate formation, providing references for hydro-thermo-mechanical responses of the reservoir rock to temperature changes within future enhanced geothermal systems as located in the Southern German Molasse Basin. Experiments deriving the changes in the primary (water-accessible) pore volume and the bulk volume of three water-saturated rock samples were conducted via loading the samples to defined stress states (σ3 of 15 MPa; σ1 of up to 75 MPa ), respectively, and then cycling sample temperature between 30 °C and defined levels up to 120 °C at a sustained pore pressure of 0.5 MPa. Permeability was measured under isothermal conditions at each attained temperature. The primary voids dilated upon heating and partly contracted via cooling in each applied temperature cycle yielding thereby residual dilation. However, the concomitant bulk sample deformation manifested residual compaction. The permeability increased with increasing temperature and showed residual decreases by the end of the temperature cycling tests. Flow of pore fluid from the primary voids into the secondary voids at increased temperatures due to the decreased fluid viscosity mimicked irreversible dilation in the primary voids. The interplay between pressure solution-driven compaction and thermal expansion in rock solids was considered to account for the sample deformation and the development of permeability. It is presumable that the pressure solution-driven compaction and the contraction in rock solids would influence the long-term hydro-thermo-mechanical behavior of the Upper Jurassic carbonate reservoir rocks in the cooling process related to fluid injection at the geothermal systems located therein.

Description: This dataset provides mechanical test data for quartz sand (“MAM1ST-300”, Sibelco, Mol, Belgium), gypsum powder (plaster; “Goldband”, Knauf), kaolin clay powder, garnet sand, and mixtures of quartz sand and gypsum powder, used at the Analogue Laboratory of the Department of Geography at the Vrije Universiteit Brussel, Brussels, Belgium, for simulating brittle rocks in the upper crust (Poppe et al., 2019). The measured properties are density ρ, tensile strength T0, shear strength σ, obtained by density measurements, ring-shear tests (RST; at Helmholtz Centre Potsdam GFZ, Germany), direct shear tests, traction tests (at University of Maine, Le Mans, France) and extension tests. The obtained tensile strengths and shear strengths reconstruct two-dimensional failure envelopes for each material. By fitting linear Coulomb and non-linear combined Griffith failure criteria to the characterised failure envelopes (Jaeger et al., 2007), the internal friction coefficient µC, Coulomb cohesion CC and Griffith cohesion CG are obtained. The influence of the material emplacement technique has been investigated in Poppe et al. (2021) to which this data set is supplementary, by repeat characterisation of the above physical parameters under three emplacement conditions, i.e. sieving, pouring (non-dried state) and compaction after pouring (oven-dried state). We find that densities of the materials and mixtures range from ~1600 kg.m³ (sieved) and ~1700 kg.m³ (compacted) for pure quartz sand to ~600 kg.m³ (poured) to ~900 kg.m³ (compacted) for pure plaster. Tensile strengths range from ~166 Pa (sand) to ~425 Pa (plaster). Velocity ring-shear tests on a 90 wt% quartz sand – 10 wt% plaster mixture show a minor shear rate-weakening of 〈2% per ten-fold increase in shear velocity. The materials show a behavior ranging from Mohr-Coulomb behavior for the materials with coarser grain size (sands) to combined Griffith-Mohr-Coulomb behavior for the powder materials (plaster, kaolin), with the sand-plaster mixtures occupying a spectrum between both end-members. Peak friction coefficients range from ~0.5 (sand) to ~0.6 (plaster) with a maximum of ~0.9 (80:20 wt% sand:plaster), peak Coulomb cohesions range from 13 Pa (sand) to 248 Pa (plaster), peak Griffith cohesions range from ~10 Pa (sand) to ~425 Pa (plaster).

Description: We explored the diversity and community composition of bacteria along a vertical gradient in Lake Issyk Kul, Kyrgyzstan, one of the world's largest and deepest brackish lakes. We identified 4904 bacterial amplicon sequence variants (ASVs) based on the 16S rRNA gene analysis and determined significant changes in the composition, responding mainly to depth and salinity. A higher abundance of Proteobacteria and Bacteroidetes was observed in the surface waters and lake tributaries. Cyanobacteria were more abundant in the deep chlorophyll maximum (DCM) from 28.5 to 128 m, while Planctomycetes and Chloroflexi were dominant in the deepest layers, from 128 to 600 m. According to our machine learning analyses, depth and temperature were the most critical environmental factors, with strong effects on Proteobacteria, Planctomycetes, and Chloroflexi, while oxygen was associated with the variations in Cyanobacteria. We also observed that with increasing depth, the alpha diversity values increased. The dominance of Planctomycetes and Chloroflexi in the deepest layers can only be seen in a few lakes of the world. However, the lake is facing increasing anthropogenic and climatic pressure. There is an urgent need to understand better the ecological role and function of these unique deep‐water microbial communities.

Description: Herbivory by barnacle geese (Branta leucopsis) alters the vegetation cover and reduces ecosystem productivity in high-Arctic peatlands, limiting the carbon sink strength of these ecosystems. Here we investigate how herbivory-induced vegetation changes affect the activities of peat soil microbiota using metagenomics, metatranscriptomics and targeted metabolomics in a comparison of fenced exclosures and nearby grazed sites. Our results show that a different vegetation with a high proportion of vascular plants developed due to reduced herbivory, resulting in a larger and more diverse input of polysaccharides to the soil at exclosed study sites. This coincided with higher sugar and amino acid concentrations in the soil at this site as well as the establishment of a more abundant and active microbiota, including saprotrophic fungi with broad substrate ranges, like Helotiales (Ascomycota) and Agaricales (Basidiomycota). A detailed description of fungal transcriptional profiles revealed higher gene expression for cellulose, hemicellulose, pectin, lignin and chitin degradation at herbivory-exclosed sites. Furthermore, we observed an increase in the number of genes and transcripts for predatory eukaryotes such as Entomobryomorpha (Arthropoda). We conclude that in the absence of herbivory, the development of a vascular vegetation alters the soil polysaccharide composition and supports larger and more active populations of fungi and predatory eukaryotes.

Description: The Lindero gold deposit is located in the Southern Puna plateau, northwest Argentina. The deposit is centered in a cluster of six subvolcanic intrusions emplaced at the margin of the Arizaro Basin. Three alteration types were recognized: (i) Ca–Na silicate (clinopyroxene + magnetite + K-feldspar + quartz + calcite ± plagioclase), (ii) K-silicate (K-feldspar + quartz + magnetite ± biotite ± anhydrite) and (iii) chlorite-calcite alteration. The highest ore grades are linked to the K-silicate alteration. The proven plus probable reserves of Lindero are 84,226 t with average grades of 0.63 g/t Au and 0.11% Cu. A previous study assigned Lindero to the iron oxide copper-gold (IOCG) deposit type but many features of Lindero suggest that it is a porphyry gold deposit, including (i) the temporal and spatial link between alteration and the intrusive bodies, (ii) the alteration distribution pattern, particularly the small volume of rock affected by Ca–Na silicate alteration, (iii) the Au-rich and Cu-poor mineralization style. The magmatic complex at Lindero comprises an early-mineral unit (FPD), four inter-mineral units (CPD1, PBFD, CPD2 and DDP) and one post-mineral unit (PMI). In-situ U/Pb SIMS dating of the oldest (FPD), an intermediate (PBFD) and the youngest (DDP) intrusive units, confirms a middle Miocene age. The weighted mean ages of the oldest and youngest units are indistinguishable, with 15.36 ± 0.13 Ma (n = 21) and 15.47 ± 0.11 Ma (n = 16), respectively. Individual ages from each unit range by ~1 m.y. and the overall spread of zircon ages is 15.92 ± 0.23 to 14.44 ± 0.33 Ma. We suggest that emplacement of the subvolcanic stocks took place within this span time, likely at the lower end of this range (15.0–14.4 Ma). Two 40Ar/39Ar ages of hydrothermal biotites from the K-silicate alteration (14.99 ± 0.16 Ma and 14.93 ± 0.12 Ma) indicate that hydrothermal alteration began practically simultaneously with the emplacement of the porphyry units. All of the intrusive units are similar compositionally. They show a fine- to medium-grained porphyric texture (1–4 mm) comprising plagioclase, amphibole, clinopyroxene and scarce quartz phenocrysts (40–55 vol % of phenocrysts) in a K-feldspar ± quartz microcrystalline (0.02–0.07 mm) groundmass, except in the post-mineral unit which has a cryptocrystalline groundmass. Whole-rock analyses reveal a narrow range of dioritic composition (58.6–61.9 wt % SiO2) and high-K calc-alkaline character for all units. Trace element features (low Ba/Nb ratios, high Nb) of the Lindero magmas indicate a back-arc affinity, similar to those from the Southern Puna and distinct from the Central Volcanic Zone (CVZ) frontal arc. The Sr and Nd isotope ratios (87Sr/86Sr = 0.706042 to 0.706607; 143Nd/144Nd = 0.512501 to 0.512582) from Lindero intrusives are also similar to Southern Puna back-arc volcanic rocks. The Pb isotope ratios of Lindero (206Pb/204Pb = 18.79 to 18.83; 207Pb/204Pb = 15.60 to 15.63; 208Pb/204Pb = 38.66 to 38.74) overlap with both back-arc and arc magmas in the CVZ. The narrow age range, spatial association and uniform chemical and isotopic composition of Lindero porphyry units suggest that were derived from a common magma source, which underwent fractionation and/or crustal assimilation before emplacement as suggest by the low concentrations of Mg, Cr, Ni and Sr. The Lindero porphyry units show chemical and isotopic similarities with those from porphyry gold deposits in the Maricunga belt, Chile, and with the porphyry copper deposits of Argentina located in a back-arc setting; however, they differ from porphyry copper deposits in the frontal-arc setting of Chile, notably by the lack of an adakite-like signature (high Sr/Y ratio).

Description: Here, we present the source mechanism and rupture process for the destructive 24 January 2020 Mw 6.7 Doğanyol–Sivrice earthquake at the East Anatolian Fault Zone (EAFZ, Turkey), obtained from seismological waveform analysis and space geodetic observations. Multi-data analyses and modelling in the present study provide fundamental data and strong constraints for retrieving complex source mechanism of an earthquake and its spatiotemporal slip characteristics along the ruptured segment of fault. The acquired slip model of this earthquake reveals heterogeneous slip distribution along strike N244°E of the fault plane dipping NW (68°) with duration of the source time function (STF) and low stress drop value (Δσ) of ~25 s and ~ 6 bars, respectively. Back-projection analysis validates fault length (L) stretching along strike for a distance of ~75 km and supports predominant south-westerly bilateral rupture propagation with a variable rupture velocity (Vr) of ~2.3–3.4 km/s along with two main patches, presumably a sequence of two asperities being ruptured following the surface trace of the EAFZ. The distribution of aftershocks based on the analysis of two months long data consistently confirms spreading of seismicity along the ruptured fault. The evaluation of Interferometric Synthetic Aperture Radar (InSAR) data reveals that left-lateral co-seismic slip and significant deformation extends for ~20 km on either side of the fault with evident post-seismic displacement. Yet, no significant vertical offsets were observed as GNSS stations detected only horizontal motions. Coda-wave analysis as an independent tool also confirms moment magnitude of Mw 6.7. Our results highlight a case of a damaging earthquake and enhance our understanding of earthquake mechanics, continental deformation and augmented earthquake risk on the EAFZ.

Description: Located between the Northern Province of Zambia and the southeastern Katanga Province of the Democratic Republic of Congo, Lakes Mweru and Mweru Wantipa are part of the southwest extension of the East African Rift System (EARS). Fault analysis reveals that, since the Miocene, movements along the active Mweru-Mweru Wantipa Fault System (MMFS) have been largely responsible for the reorganization of the landscape and the drainage patterns across the western branch of the EARS. To investigate the spatial and temporal patterns of fluvial-lacustrine landscape development, we determined in-situ cosmogenic 10Be and 26Al using Accelerator Mass Spectrometry. A total of twenty-six quartzitic bedrock samples were collected from knickpoints across the Mporokoso Plateau (south of Lake Mweru) and the eastern part of the Kundelungu Plateau (north of Lake Mweru). Samples from the Mporokoso Plateau and close to the MMFS provide evidence of temporary burial. By contrast, surfaces located far from the MMFS appear to have remained uncovered since their initial exposure as they show consistent 10Be and 26Al exposure ages ranging up to ~830 ka. Reconciliation of the observed burial patterns with morphotectonic and stratigraphic analysis reveals the existence of an extensive paleo-lake during the Pleistocene. Through hypsometric analyses of the dated knickpoints, the potential maximum water level of the paleo-lake is constrained to ~1200 m asl. High denudation rates (up to ~40 mm ka−1) along the eastern Kundelungu Plateau suggest that footwall uplift, resulting from normal faulting, caused rapid river incision, thereby controlling paleo-lake drainage. The complex exposure histories recorded by 10Be and 26Al may be explained because of lake water-level fluctuations caused by active normal faulting along the MMFS coupled with intense climate variations across southeastern Africa.

Description: In the Mesoamerican region, arid or hydrological variable conditions are commonly interpreted from 4 ka onwards. It is not well known how these changes modified the Mesoamerican monsoon system, which were the main atmospheric-oceanic forcings involved and their effect in the Pre-Classic Mesoamerican societies' history. Here, we study the possible link between paleoclimatic changes and decreased social development of societies in Mesoamerica during the Pre-Classic period (4.3 ka to 2.2 ka), which correspond to the Middle-Late Holocene transition. We also describe the principal oceanic-atmospheric mechanism related. We employed a partly laminated sediment sequence from La Alberca maar lake in the central Mexico highlands by means of environmental magnetism and comparing versus X-ray fluorescence (XRF), pollen, and δ18O analyses. Increased concentrations and preservation of ferrimagnetic minerals and enhanced detrital load as described by the XRF Ti counts reveal the occurrence of variable hydrological conditions between ∼4.4 ka to 2.2 ka. These conditions coincide with the onset of high-frequency latitudinal variations of the Intertropical Convergence Zone (ITCZ) and the rise of ENSO and Pacific decadal oscillation activity. We suggest that variable hydrological conditions affected the development of Mesoamerican agrarian societies stressing agricultural production during the Pre-Classic period.

Description: The Changning MS6.0 earthquake and its moderate to strong aftershocks, which occurred in the axial area of Changning anticline, exhibit different features with the moderate to strong earthquakes that occurred in the southern syncline area nearby, although these two areas are only a dozen kilometers away. Whether this difference is only caused by different fault structures, or caused by local change is still a matter of debate. In order to answer this question, basing on the correction of small earthquake location and seismic velocity structure through double-difference tomography inversion, this paper determined the fine structure of the crustal stress field by using comprehensive focal mechanism solutions, and analyzed its mechanical consistency with the focal mechanism solutions of moderate to strong earthquakes. It is found that for the different subareas of Changning area, the maximum principal stress remains horizontal, and its azimuth remains almost East-West oriented although it has a small clockwise rotation from north to south; meanwhile, the stress regime exhibit a significant local change, which is thrust stress regime for the axial area of Changning anticline, against strike-slip stress regime for the southern syncline area. The stress fields in these two subareas highly accord with the focal mechanism solutions of moderate to strong earthquakes in the corresponding area, but poorly accord with, or even contradict that in the non-corresponding area, which indicates that the local stress change of stress field is the necessary mechanical basis for the complex seismicity behavior in Changning area. Additional rock mechanics analysis points out that lateral difference of Poisson's ratio of rock is probably the main cause of this local change of stress field. This paper also discusses the seismogenic fault structure of Changning MS6.0 earthquake sequence, and suggests the activation of the basement fault(s) in the depth range of 6 to 9 km in the axial area of Changning anticline driven by regional stress field is the potential cause of the occurrence of Changning MS6.0 earthquake sequence.

Description: We discuss the important role of tangential stretching in the Central Alps highlighting that the Alps are a truly three-dimensional orogen. A review of pressure-temperature (P-T) conditions allows us to define three major breaks in metamorphic pressure (P-breaks) across the nappe pile. We constrain the kinematics of mylonites associated with these P-breaks and report eight new Rbsingle bondSr multi-mineral isochrons that define the age of the mylonites. Kinematic data and Rbsingle bondSr geochronology indicate that the timing of top-SE normal shearing in the Avers-Turba mylonite zone (≥45–34 Ma; P-break1) and in a zone of distributed top-E normal shearing (〉35–30 Ma) above the (ultra)high-P Adula nappe of the distal, thinned European margin (P-breaks 2 and 3). The ages from both sets of mylonite are grading into each other at about 35–34 Ma. All ages appear to postdate high-P metamorphism in the Pennine nappes but are, in part, coeval with and predate (ultra)high-P metamorphism in the underlying Adula nappe of the distal European (Helvetic) margin. The oldest Rbsingle bondSr age of 42.3 ± 2.5 Ma (2σ uncertainties) dates the waning stage of mylonitization and indicates that the Avers-Turba mylonite zone started to operate ≥45 Ma, and predated the exhumation of the Adula nappe by ~10 Ma. We suggest that the motion in the Avers-Turba mylonite zone overlapped with backfolding of the Schams nappe in an extrusion wedge. When this process started, the Adula nappe was still being underthrust/underplated. The ages for distributed top-E normal shearing are contemporaneous with thrusting of the Adula nappe on top of distinctly lower-P Helvetic nappes. When the Adula nappe was being thrust onto non-high-P nappes the necessary reduction of its overburden was largely accomplished by distributed top-E normal faulting above the Adula nappe, and possibly still ongoing top-SE normal shearing. We discuss that major normal shearing occurred during lithospheric shortening. Our data indicate considerable tangential (out-of-plane) movements during overall top-N/NW thrust propagation in the Central Alps and have implications for current tectonic models of the Alps.

Description: Landslide dam failures have devastating capability to cause significant hazards to human lives and infrastructure along their flooding paths. Recent studies have explored such hazards based on environmental seismology to analyze the process of evolution using the time-frequency characteristics of seismic signals. However, most research has focused on reconstructing individual processes (e.g., debris flows, landslides, and floods). Previous studies on a comprehensive analysis of the entire hazard chain process have been limited. Challenges lie in the integration of seismic signals with different energy levels during different hazard stages. To address this issue, post-hazard surveys, remote sensing, and seismic signals were obtained in this study to comprehensively analyze the evolution process of the Danba landslide dam failure hazard chain of June 17, 2020, in China. We developed weak-signal processing using a band-pass filter, empirical mode decomposition, fast Fourier transform, and short-time Fourier transform to process and analyze the seismic data and accurately extract the signals for the debris flow, landslide, flood, and noise attenuation in the hazard chain. The evolution process of each stage in the hazard chain was then interpreted. The debris flow, landslide, barrier lake bursting, and flood routing were analyzed to determine their evolution modes. In addition, the reactivation of ancient landslides downstream caused by flood erosion was also identified, with stage explanations. This method provides new ideas for interpreting the hazard chain processes and evolution modes of landslide dam failure hazard chains and theoretical guidance for future hazard early warning and mitigation.