ALBERT

Description: Borehole measurements or downhole logging is a powerful method to in-situ gain quasi-continuous profiles of physical, chemical and structural rock parameters with high depth accuracy. It is widely used in both academic research and commercial exploration for oil and gas, mining industry, geothermal and water engineering. The GFZ section Scientific Drilling facilitates logging in two ways, first through service and applying a set of downhole instruments and second through developing novel methods and tools. Logging support is provided to scientific projects and covers assistance with planning and logistics of downhole logging programs, logging service through operating a versatile set of own downhole sondes, including geophysical and structural logging tools, a seismic chain and a fluid sampler. In order to expand the possibilities of in-situ borehole information new tools are developed jointly with academic and industrial partners. The most advanced sonde development strives to image geological structures by using high-resolution borehole seismics to explore hydrocarbons or geothermal resources by detecting thin layers and faults. The SPWD (Seismic Prediction While Drilling) borehole prototype sonde combines seismic sources and receivers in one device to improve the resolution. Two downhole test sites, the KTB-Deep Crustal Lab in Windischeschenbach and the GFZ Underground Lab in the mine “Reiche Zeche” in Freiberg offer unique in-situ conditions for experiments and tests of the borehole equipment.

Description: The ability of any satellite gravity mission concept to monitor mass transport processes in the Earth system is typically tested well ahead of its implementation by means of various simulation studies. Those studies often extend from the simulation of realistic orbits and instrumental data all the way down to the retrieval of global gravity field solution time-series. Basic requirement for all these simulations are realistic representations of the spatio-temporal mass variability in the different sub-systems of the Earth, as a source model for the orbit computations. For such simulations, a suitable source model is required to represent (i) high-frequency (i.e., subdaily to weekly) mass variability in the atmosphere and oceans, in order to realistically include the effects of temporal aliasing due to non-tidal high-frequency mass variability into the retrieved gravity fields. In parallel, (ii) low-frequency (i.e., monthly to interannual) variability needs to be modelled with realistic amplitudes, particularly at small spatial scales, in order to assess to what extent a new mission concept might provide further insight into physical processes currently not observable. The new source model documented here attempts to fulfil both requirements: Based on ECMWF’s recent atmospheric reanalysis ERA-Interim and corresponding simulations from numerical models of the other Earth system components, it offers spherical harmonic coefficients of the time-variable global gravity field due to mass variability in atmosphere, oceans, the terrestrial hydrosphere including the ice-sheets and glaciers, as well as the solid Earth. Simulated features range from sub-daily to multiyear periods with a spatial resolution of spherical harmonics degree and order 180 over a period of 12 years. In addition to the source model, a de-aliasing model for atmospheric and oceanic high-frequency variability with augmented systematic and random noise is required for a realistic simulation of the gravity field retrieval process, whose necessary error characteristics are discussed. The documentation of the updated ESA Earth System Model (updated ESM) for gravity mission simulation studies is organized as follows: The characteristics of the updated ESM along with some basic validation is presented in Volume 1. A detailed comparison to the original ESA ESM (Gruber et al., 2011) is provided in Volume 2, while Volume 3 contains the description of a strategy to derive realistic errors for the de-aliasing model of high-frequency mass variability in atmosphere and ocean.

Description: Naturgefahren werden in erster Linie als Risiken gesehen, die vom Menschen nicht verursacht oder beeinflusst werden können. Diese Einschätzung trifft aber nicht durchgängig zu. So spielen bei Überschwemmungen, Dürren und den Auswirkungen des Klimawandels menschliche Aktivitäten oft eine entscheidende Rolle. Das betrifft zum Beispiel die Einflüsse hydrogeologischer Veränderungen durch Flussregulierungen und Eindeichungen oder Veränderungen durch intensive Landnutzungsmaßnahmen wie Waldrodungen oder Überweidungen.

Description: The integrated plate boundary in Chile (IPOC) combines 15 broadband stations with strong-motion sensors, GPS, strain sensors and magneto-telluric stations. The Chilean subduction zone setting provides a high background rate of seismicity (crustal, intermediate depth, and plate interface) in a region with exceptionally low ambient noise, particularly at higher frequencies. We have deployed seismic mini-arrays in the vicinity of IPOC stations PB02 and PB07, and installed a third array to the east of these stations near the village of Quillagua, such that all three arrays form a triangle. Each array has 10 elements and an aperture in the km range. The study area lies just to the north of the northern boundary of the rupture area of the Tocopilla earthquake of 2007 Mw=7.7) and just above or slightly to the east of the downdip limit of plate interface seismicity. Installing the mini-arrays in the area of the existing IPOC has the following advantages: • Independent knowledge of background structure and seismicity from existing and ongoing studies. • Should any transients or other unusual signals be found in the array data, we can look for anomalous signals in geodetic and MT recordings, which will help to narrow down possible underlying mechanisms.

Description: With the rapidly increasing utilization of the subsurface, either for exploitation of natural resources or long-term storage of waste products, it is of paramount importance to understand this so far understudied environment. Over the last two decades new findings have shown that microbes mediate many processes that were previously considered as abiotic. Exploration of the so-called Deep Biosphere is only possible through drilling. With regard to drilling operations and sample processing, microbiology has different requirements than many other scientific disciplines, the most important one being contamination control because drilling fluid tends to infiltrate the drill core and renders the material unsuitable for microbiological analyses. There are different ways to assess the infiltration of drill fluid, each one has its specific advantages and disadvantages. Another important aspect of deep biosphere research is the necessity to process samples as quickly as possible after retrieval to avoid any changes in the microbial community. These requirements add some complications to drilling operations, therefore the addition of a geomicrobiological component is not always appreciated by all members of a science party. However, knowledge about the drivers of diagenetic processes and accurate assessment of the contamination of the core by drilling fluids are valuable information for other disciplines as well.

Description: This paper presents the first published 3D geomechanical modelling study of the CO2CRC Otway Project, located in the state of Victoria, Australia. The results of this work contribute to one of the main objectives of the CO2CRC, which is to demonstrate the feasibility of CO2 storage in a depleted gas reservoir. With this aim in mind, a one-way coupled flow and geomechanics model is presented, with the capability of predicting changes to the in situ stress field caused by changes in reservoir pressure owing to CO2 production and injection. A parametric study investigating the pore pressures required to reactivate key, reservoir-bounding faults has been conducted, and the results from the numerical simulation and analytical analysis are compared. The numerical simulation indicates that the critical pore fluid pressure to cause fault reactivation is 1.15 times the original pressure as opposed to 1.5 times for the comparable analytical model. Possible reasons for the differences between the numerical and analytical models can be ascribed to the higher degree of complexity incorporated in the numerical model. Heterogeneity in terms of lateral variations of hydrological and mechanical parameters, effect of topography, presence of faults and interaction between cells are considered to be the main sources for the different estimation of critical pore pressure. The numerical model, which incorporates this greater complexity, is able then to better describe the state of stress that acts in the subsurface compared with a simple 1D analytical model. Moreover, the reactivation pressures depend mainly on the state of stress described; therefore we suggest that numerical models be performed when possible.

Description: Das Zentralinstitut für Physik der Erde wurde 1969 durch Vereinigung vier bis dahin selbständiger Akademieinstitute für Geodäsie, Geodynamik, Geomagnetismus und Geotektonik gebildet. Die Forschungsarbeiten reichen einerseits von Beiträgen zur höheren Geodäsie Uber Untersuchungen zur Seismologie und geophysikalisoben Festkörperforsobung bis zu ausgewählten Problemen der Physik und Chemie des Mondes und der Planeten und andererseits von Arbeiten zur physikalischen Struktur und Dynamik der Lithosphäre, besonders der Erdkruste, bis zu strukturgeologischen und geotektonischen Untersuchungen. Die Forschungen werden in wachsendem Maße geprägt durch die Zielstellungen des internationalen Geodynamik-Projektes und bestimmt durch die Anforderungen der sozialistischen Gesellschaft hinsichtlich des wissenschaftlichen Vorlaufs und spezieller wissenschaftlicher Dienstleistungen. Die Arbeit gibt eine Übersicht über die wichtigsten Entwicklungen und Forschungsergebnisse aus dem letzten Jahrzehnt.

Description: We investigate the feedbacks between surface processes and tectonics in an extensional setting by coupling a 2‐D geodynamical model with a landscape evolution law. Focusing on the evolution of a single normal fault, we show that surface processes significantly enhance the amount of horizontal extension a fault can accommodate before being abandoned in favor of a new fault. In simulations with very slow erosion rates, a 15 km thick brittle layer extends via a succession of crosscutting short‐lived faults (heave 〈 5 km). By contrast, when erosion rates are comparable to the regional extension velocity, deformation is accommodated on long‐lived faults (heave 〉10 km). Using simple scaling arguments, we quantify the effect of surface mass removal on the force balance acting on a growing normal fault. This leads us to propose that the major range‐bounding normal faults observed in many continental rifts owe their large offsets to erosional and depositional processes.

Description: With the upcoming launch of the next generation of hyperspectral satellites that will routinely deliver high spectral resolution images for the entire globe (e.g. EnMAP, HISUI, HyspIRI, HypXIM, PRISMA), an increasing demand for the availability/accessibility of hyperspectral soil products is coming from the geoscience community. Indeed, many robust methods for the prediction of soil properties based on imaging spectroscopy already exist and have been successfully used for a wide range of soil mapping airborne applications. Nevertheless, these methods require expert know-how and fine-tuning, which makes them used sparingly. More developments are needed toward easy-to-access soil toolboxes as a major step toward the operational use of hyperspectral soil products for Earth's surface processes monitoring and modelling, to allow non-experienced users to obtain new information based on non-expensive software packages where repeatability of the results is an important prerequisite. In this frame, based on the EU-FP7 EUFAR (European Facility for Airborne Research) project and EnMAP satellite science program, higher performing soil algorithms were developed at the GFZ German Research Center for Geosciences as demonstrators for end-to-end processing chains with harmonized quality measures. The algorithms were built-in into the HYSOMA (Hyperspectral SOil MApper) software interface, providing an experimental platform for soil mapping applications of hyperspectral imagery that gives the choice of multiple algorithms for each soil parameter. The software interface focuses on fully automatic generation of semi-quantitative soil maps such as soil moisture, soil organic matter, iron oxide, clay content, and carbonate content. Additionally, a field calibration option calculates fully quantitative soil maps provided ground truth soil data are available. Implemented soil algorithms have been tested and validated using extensive in-situ ground truth data sets. The source of the HYSOMA code was developed as standalone IDL software to allow easy implementation in the hyperspectral and non-hyperspectral communities. Indeed, within the hyperspectral community, IDL language is very widely used, and for non-expert users that do not have an ENVI license, such software can be executed as a binary version using the free IDL virtual machine under various operating systems. Based on the growing interest of users in the software interface, the experimental software was adapted for public release version in 2012, and since then ~80 users of hyperspectral soil products downloaded the soil algorithms at www.gfz-potsdam.de/hysoma. The software interface was distributed for free as IDL plug-ins under the IDL-virtual machine. Up-to-now distribution of HYSOMA was based on a close source license model, for non-commercial and educational purposes. Currently, the HYSOMA is being under further development in the context of the EnMAP satellite mission, for extension and implementation in the EnMAP Box as EnSoMAP (EnMAP SOil MAPper). The EnMAP Box is a freely available, platform-independent software distributed under an open source license. In the presentation we will focus on an update of the HYSOMA software interface status and upcoming implementation in the EnMAP Box. Scientific software validation, associated publication record and users responses as well as software management and transition to open source will be discussed.

Description: GRACE (Gravity Recovery and Climate Experiment) ist ein gemeinsames Projekt zwischen der USRaumfahrtbehörde (NASA) und dem Deutschen Zentrum für Luft- und Raumfahrt (DLR). Mit zwei baugleichen Satelliten, die sich seit 2002 auf derselben Bahn folgen, wird das primäre wissenschaftliche Ziel verfolgt, das Schwerefeld der Erde und dessen zeitliche Veränderungen mit nie da gewesener Genauigkeit zu vermessen. Nach 14 Jahren Betrieb werden die Satelliten vorraussichtlich ab 2016 keine Messdaten mehr liefern, mit GRACE-FO werden die Datensätze ab 2017 fortgesetzt – die deutschen Beiträge dazu werden vom GFZ geleitet.

Description: Splay faults, large thrust faults emerging from the plate boundary to the seafloor in subduction zones, are considered to enhance tsunami generation by transferring slip from the very shallow dip of the megathrust onto steeper faults, thus increasing vertical displacement of the seafloor. These structures are predominantly found offshore, and are therefore difficult to detect in seismicity studies, as most seismometer stations are located onshore. The Mw (moment magnitude) 8.8 Maule earthquake on 27 February 2010 affected ~500 km of the central Chilean margin. In response to this event, a network of 30 ocean-bottom seismometers was deployed for a 3 month period north of the main shock where the highest coseismic slip rates were detected, and combined with land station data providing onshore as well as offshore coverage of the northern part of the rupture area. The aftershock seismicity in the northern part of the survey area reveals, for the first time, a well-resolved seismically active splay fault in the submarine forearc. Application of critical taper theory analysis suggests that in the northernmost part of the rupture zone, coseismic slip likely propagated along the splay fault and not the subduction thrust fault, while in the southern part it propagated along the subduction thrust fault and not the splay fault. The possibility of splay faults being activated in some segments of the rupture zone but not others should be considered when modeling slip distributions.

Description: Generating data catalogue pages from ISO19139, GMCD-DIF and Datacite metadata

Description: Due to its remoteness, the CO2 Lab close to the town of Longyearbyen on Svalbard presents a unique opportunity to demonstrate the entire CO2 value chain based on its closed energy system. The formation considered as potential CO2 storage unit consists of mixed sandstone and shale beds, presenting itself as a fractured, low-permeability reservoir. A geophone network surrounding the injection well has been installed to locate microseismic events during injection tests and to estimate background seismicity. During the first water injection in 2010, a microseismic event (M ∼ 1) was recorded and located close to the injection well, followed by a series of aftershocks. Later injection tests did not generate any detectable microseismic events; nevertheless, pressure and flow rate showed a pattern characteristic for fracture opening potentially indicating “aseismic” fracture propagation. Records of ambient seismic noise are analysed by a cross-correlation method in order to reconstruct the impulse functions between sensors. The daily cross-correlations are dominated by tube wave signals originating from the bottom of the well showing a sudden increase of activity. We also demonstrate a noise cancellation method exhibiting great potential towards cancellation of electromagnetic and cultural noise. Albeit several difficulties that were approached at the CO2 Lab, new knowledge and guidelines for best practice containment monitoring using seismic methods in the Arctic could be developed.

Description: Deutschland hat im letzten Jahr das von der Europäischen Union gesteckte Ziel erreicht, 3% des Bruttoinlandsproduktes für Wissenschaft bereitzustellen. Konkret sind das rund 80 Mrd. €, von denen etwa ein Drittel aus öffentlichen Kassen kommt. Wenn der Steuerzahler derart gewaltige Summen bereitstellt, dann muss es sich die Wissenschaft gefallen lassen, über deren Verwendung Rechenschaft abzulegen. Zur Bewertung der Forschungsleistung existiert inzwischen eine große Zahl verschiedener Parameter. Richtig angewendet und jeweils fachspezifisch ausgewertet, geben diese Maßzahlen Auskunft über die wissenschaftliche Leistungsfähigkeit, die allerdings grundsätzlich durch ein qualitatives Peer-Review- Verfahren ergänzt werden sollte. Denn eine rein quantitative Bewertung kann zu völlig falschen Aussagen und daraus abgeleitetem falschem Handeln führen.

Description: 14. Februar – Valentinstag. Für viele ein romantischer Pflichttermin, für andere nur ein weiterer Erfolgstag der Grußkartenmafia. Für uns jedoch hieß es zum vierten Jahr in Folge: Vorhang auf für den regionalen Vorentscheid Brandenburg -Berlin von Famelab.

Description: Passive continental margins offer the unique opportunity to study the processes involved in continental extension and break up as well as the role of hot-spot related magmatism. We conducted combined on- and offshore seismic experiments in Northern Namibia designed to characterize the Southern African passive margin at the interaction with the Walvis Ridge, to assess the interaction of the presumed plume with continental lithosphere and to determine the deep structure of the transition from the coastal fold belt to the stable craton, where the Walvis Ridge hits the African continent. The seismic project integrated three experiments, (A) an onshore, coast-parallel refraction seismic profile, (B) two onshore-offshore wide-angle seismic transects, and (C) a combined on- and offshore seismic experiment to image the sub-Moho velocity (Pn tomography) at the ocean-continent transition (Fig. 1). The knowledge of the lithospheric structure of the margin together with results from other geoscientific studies (e.g., conducted within the SPPSAMPLE, DFG Priority Program 1375, South Atlantic Margin Processes and Links with onshore Evolution) will help to address fundamental questions such as, how continental crust and plume head interact, what the extent and volumes of magmatic underplating is, and how and which inherited (continental) structures might have been involved and utilized in the break-up process.

Description: A joint earthquake source inversion technique is presented that uses InSAR and long-period teleseismic data, and, for the first time, takes 3-D Earth structure into account when modelling seismic surface and body waves. Ten average source parameters (Moment, latitude, longitude, depth, strike, dip, rake, length, width and slip) are estimated; hence, the technique is potentially useful for rapid source inversions of moderate magnitude earthquakes using multiple data sets. Unwrapped interferograms and long-period seismic data are jointly inverted for the location, fault geometry and seismic moment, using a hybrid downhill Powell–Monte Carlo algorithm. While the InSAR data are modelled assuming a rectangular dislocation in a homogeneous half-space, seismic data are modelled using the spectral element method for a 3-D earth model. The effect of noise and lateral heterogeneity on the inversions is investigated by carrying out realistic synthetic tests for various earthquakes with different faulting mechanisms and magnitude (Mw 6.0–6.6). Synthetic tests highlight the improvement in the constraint of fault geometry (strike, dip and rake) and moment when InSAR and seismic data are combined. Tests comparing the effect of using a 1-D or 3-D earth model show that long-period surface waves are more sensitive than long-period body waves to the change in earth model. Incorrect source parameters, particularly incorrect fault dip angles, can compensate for systematic errors in the assumed Earth structure, leading to an acceptable data fit despite large discrepancies in source parameters. Three real earthquakes are also investigated: Eureka Valley, California (1993 May 17, Mw 6.0), Aiquile, Bolivia (1998 February 22, Mw 6.6) and Zarand, Iran (2005 May 22, Mw 6.5). These events are located in different tectonic environments and show large discrepancies between InSAR and seismically determined source models. Despite the 40–50 km discrepancies in location between previous geodetic and seismic estimates for the Eureka Valley and Aiquile earthquakes, the seismic data are found to be compatible with the InSAR location. A 30° difference in strike between InSAR and seismic-derived source models is also resolved when taking 3-D Earth structure into account in the analysis of the Eureka Valley earthquake. The combination of both InSAR and seismic data further constrains the dip for the Zarand earthquake, and in all cases the seismic moment is more robustly constrained in the joint inversions than in the individual data set inversions. Unmodelled lateral heterogeneities in Earth and the models could partly explain some of the observed source parameter discrepancies related to the seismic data.

Description: This publication is a result of the 12th TRACE conference (Tree Rings in Archaeology, Climatology and Ecology) organized by the Department of Agriculture, Forests, Nature and Energy (DAFNE) of the Università della Tuscia (Viterbo, Italy) on May 08th – 11th 2013 in Viterbo, Italy. [...] A total of 20 manuscripts were submitted. After review 19 short papers are published in this volume, giving an overview of the wide spectrum of fields in tree-ring research.

Description: Cross-correlation of continuous broadband records allows the retrieval of body waves at teleseismic distances. These continuous records mainly contain low-amplitude background noise that comes from ocean–crust interactions, although there are also many transient events of different magnitudes and their coda associated with reverberation and/or scattering. We present an analysis at the global scale of these different contributions in the context of body-wave retrieval using the cross-correlation technique. Specifically, we compare the correlation of long codas after strong earthquakes with those of the quietest days. In the long period range (25–100 s), several phases that propagate in the deep Earth are observed in the correlations of the signals recorded after earthquakes, with some of these phases showing non-physical polarization. At the same time, the global section of correlations shows a series of spurious branches. These features are reproduced with synthetic correlations. A stack of the quietest days of the year shows that body waves are still present, with relative amplitudes that are closer to those expected for the actual Earth response. When considering shorter periods (5–10 s), the reconstruction of the deep phases is not affected by the earthquake coda, due to the dominance of scattering over reverberation.

Description: Reassessment of travel time data from an exceptionally dense, amphibious, temporary seismic network on- and offshore Central and Eastern Java (MERAMEX) confirms the accretionary nature of the crust in this segment of the Sunda subduction zone (109.5–111.5E). Traveltime data of P- and S-waves of 244 local earthquakes were tomographically inverted, following a staggered inversion approach. The resolution of the inversion was inspected by utilizing synthetic recovery tests and analyzing the model resolution matrix. The resulting images show a highly asymmetrical crustal structure. The images can be interpreted to show a continental fragment of presumably Gondwana origin in the coastal area (east of 110E), which has been accreted to the Sundaland margin. An interlaced anomaly of high seismic velocities indicating mafic material can be interpreted to be the mantle part of the continental fragment, or part of obducted oceanic lithosphere. Lower than average crustal velocities of the Java crust are likely to reflect ophiolitic and metamorphic rocks of a subduction melange.

Description: The Lorca 2011 seismic series was recorded by an unprecedented set of high quality on scale broadband seismograms and strong motion accelerograms. The waveforms from permanent and temporary broadband seismic networks deployed in the region by different institutions allowed to invert regional moment tensor for the fore, main and largest aftershock of the complete seismic sequence. Using double-difference algorithm we have performed a precise relocation of the seismic series, where body wave travel times from strong ground motion accelerograms were included in the data set. Regional moment tensor inversion for the three main events show similar oblique-reverse faulting regime with a northeast-southwest fault orientation. The scalar seismic moment, moment magnitude and focal depth retrieved from the inversion yield the following values for each event: Mo=6.5×1016 Nm (Mw = 5.2) for the mainshock, Mo=9.6×1015 Nm (Mw = 4.6) for the foreshock and Mo=7.3×1014 Nm (Mw = 3.9) for the large aftershock. The centroid depths range between 4 and 6 km. The double-difference relocation of the seismic series shows significant epicentral differences with the preliminary routine location. The epicentral solutions given by this relocation show a seismic sequence distributed following a NE–SW strike, subparallel to the Alhama de Murcia fault and compatible with the faulting parameters inverted from the moment tensor analysis. The hypocenters of the series generate a subvertical trend in depth distribution, being concentrated between 2 and 6 km. The depth distribution of the main events, which range from 4.6 to 5.5 km, is in good relationship with the faulting and depth parameters deduced from the moment tensor inversion technique. The regional moment tensor solutions for the three largest earthquakes, the epicentral distribution and the focal depths show good relationship with the surface geometry and tectonic regime of the Alhama de Murcia fault. The stress drop deduced for the mainshock gives a value ranging between 58 and 85 bars, which does not support the idea of a high stress drop release as a main factor contributing to the high ground acceleration recorded at Lorca. The PGA values observed at Lorca, which contributed to the high damage independently of structural deficiencies, could be generated mainly by shallowness and proximity to the seismic source together with a directivity effect in the seismic radiation.

Description: Im Oktober 2013 wurde nach einer einjährigen Pilotphase die GeoWunderWerkstatt (GWW) am GFZ feierlich eröffnet. Gruppen im Vor und Grundschulalter haben seitdem die Möglichkeit, sich kostenlos über Fragen der Erde und Umwelt kindgerecht zu informieren und spannende Experimente zu vielen verschiedenen naturwissenschaftlichen Themen durchzuführen. Die Nachfrage ist überwältigend: bereits im Februar 2014, nur fünf Monate nach Beginn der Initiative, waren alle für dieses Jahr zu vergebenden Termine ausgebucht. Am Ende des Projekts, dessen Laufzeit zunächst auf ein Jahr angesetzt ist, werden 647 Kinder aus 28 Gruppen an den spannenden Forschungsvormittagen am GFZ teilgenommen haben. Ein großer Erfolg für die Initiatorinnen – GFZ aktiv eben.

Description: Retreating ice fronts (as a result of a warming climate) expose large expanses of deglaciated forefield, which become colonized by microbes and plants. There has been increasing interest in characterizing the biogeochemical development of these ecosystems using a chronosequence approach. Prior to the establishment of plants, microbes use autochthonously produced and allochthonously delivered nutrients for growth. The microbial community composition is largely made up of heterotrophic microbes (both bacteria and fungi), autotrophic microbes and nitrogen-fixing diazotrophs. Microbial activity is thought to be responsible for the initial build-up of labile nutrient pools, facilitating the growth of higher order plant life in developed soils. However, it is unclear to what extent these ecosystems rely on external sources of nutrients such as ancient carbon pools and periodic nitrogen deposition. Furthermore, the seasonal variation of chronosequence dynamics and the effect of winter are largely unexplored. Modelling this ecosystem will provide a quantitative evaluation of the key processes and could guide the focus of future research. Year-round datasets combined with novel metagenomic techniques will help answer some of the pressing questions in this relatively new but rapidly expanding field, which is of growing interest in the context of future large-scale ice retreat.

Description: Satellites and global ground observation networks are the prerequisites to monitor global variations such as, e.g., climate or sea level changes or the decline of the geomagnetic field. Well-distributed ground observations in most cases are essential complements to space observations in order to gain an improved understanding of the processes underlying the observed changes. More than 80 % of the southern hemisphere are covered by oceans. Southern Africa is one of the few regions to allow for ground based observations there. The geomagnetic field shields our habitat against solar wind and cosmic rays. However, its average strength is clearly decreasing since the beginning of systematic observations 180 years ago, and a particularly weak field area is the region over and around the southern Atlantic, known as South Atlantic Anomaly. The GFZ activities regarding geomagnetic field observation in southern Africa and the larger southern Atlantic region provide a good example how regional ground observations are integral parts to investigating global processes, in this case geomagnetic core field evolution and space weather behaviour.

Description: Southern Africa in particular is a very special natural laboratory for a journey through the Earth’s geo-archive. We can study tectonic processes on Early Earth as well as continental collision and breakup; and we learn how and why the African continent was blessed with mineral resources, such as diamonds or gold. With the beginning of the 20th century, geoscientists have started to set up observatories in South Africa to record earthquakes (since 1910) or conduct magnetic national surveys (Beattie, 1909). In Africa these geo-scientific pioneers found an ideal environment to study different tectonic units such as Cratons – ancient nuclei of continents, younger fold and orogenic belts as well as sediment basins and to investigate and classify their physical properties. The physical parameters applied were (i) elastic properties of rocks, which can be resolved using seismic and seismological observations and which allow to infer density information of rock formations, (ii) electrical conductivities which can be sensed using geo-electric, magnetotelluric (MT) und magnetometer-array measurements, (iii) magnetic properties, i.e. the ability of rocks to get magnetized, und (iv) the density of rocks which can directly be measured using gravity. The geophysics groups of the German Research Centre for Geosciences (GFZ) have been very active in South Africa since 2004 and have studies imprints of past continental collisions in the Earth crust and mantle along several traverses.

Description: Für Marokko ist die Landwirtschaft ein äußerst wichtiger wirtschaftlicher Faktor. Doch die Wasserressourcen sind knapp, für die Wasserwirtschaft werden hydrologische Modelle immer wichtiger. Neben der Vorhersage von Extremereignissen soll auch die Vegetationsentwicklung überwacht werden. Wasserstandspegel und Bodenfeuchte sind dabei wichtige Parameter für die hydrologische Modellierung, die bisher nur unzureichend genau beobachtet werden. Die GFZ-Wissenschaftlerin Jamila Beckheinrich der Sektion 1.1 GPS/Galileo-Erdbeobachtung hat genau dieses im marrokanisch-deutschen Forschungsvorhaben PMARS (Programme Maroc-Allemand de Recherche Scientifique) initiiert. Unter ihrer Leitung sollen Grundlagen für eine wissenschaftliche Zusammenarbeit auf diesem Gebiet geschaffen werden.

Description: Seit genau zehn Jahren bietet die Sektion 3.3 „Chemie und Physik der Geomaterialien“ ein experimentell-analytisches Praktikum für fortgeschrittene Studenten an. Die Bachelor- oder Master-Studenten kommen meist von außerhalb – 60 bis 70% stammen aus Orten wie Karlsruhe, Tübingen, Hannover, Kiel oder Freiberg, aber auch die Universitäten Berlin und Potsdam sind vertreten.

Description: Remote sensing is an integral part of mineral exploration and mine waste monitoring today. The pool of geoscientific applications for remote sensing is rapidly growing with the advent of new spaceborne sensors such as the hyperspectral EnMAP (Environmental Mapping and Analysis Program) and the multispectral Sentinel-2 missions. The main advantage of hyperspectral data is the capability to identify surface materials via their characteristic absorption features, casually called “the spectral fingerprint” and map their spatial distribution. These characteristic absorption features can be used e.g. to map the abundance of rare earth elements, or map mineral assemblages that are characteristic for sulfide ore deposits. In addition to that, mine waste material can be characterized and mapped. South Africa and Namibia with their long mining history provide excellent natural laboratories for the development of new geoscientific applications for mineral exploration and environmental monitoring, due to the large areas affected by tailings dams and the large and remote desert areas, which hold the potential for new mineral deposit sites. Hyperspectral airborne data is widely used in South Africa and Namibia. However, it is too sparse and too expensive for certain applications such as the environmental monitoring of tailings sites. A combination of multispectral and hyperspectral spaceborne sensors has shown its potential to bridge this apparent gap in mine waste mapping and monitoring.

Description: Seit 2008 ist die Grundfinanzierung des GFZ um fast 32 Prozent gestiegen. Über Drittmittel haben sich die Gemeinkostenerträge für unser Zentrum insgesamt verdoppelt. Eine Erfolgsgeschichte: Das GFZ hat mehr Geld zur Verfügung als je zuvor. Zugleich gab es für unser Zentrum - eines der kleinsten in der Helmholtz-Gemeinschaft und doch im Bereich Erde und Umwelt das am stärksten fokussierte - einen gezielten Wunsch nach wissenschaftlich fundierter, strategischer Weiterentwicklung. Einhergehend mit der Einrichtung neuer Zentren und Sektionen sind dabei trotz der zusätzlichen Mittel die Personalausgaben überproportional gewachsen. Für die Quantifizierung von Forschungsleistung, gerechte Mittelverteilung und ein Gleichgewicht zwischen Personal-, Sach- und Investitionsausgaben gibt es Kennzahlen und Parameter, die dem GFZ-Vorstand dabei helfen, den richtigen Weg einzuschlagen. Prof. Hüttl und Dr. Schwartze äußern sich zur Weiterentwicklung des GFZ.

Description: The ability of any satellite gravity mission concept to monitor mass transport processes in the Earth system is typically tested well ahead of its implementation by means of various simulation studies. Those studies often extend from the simulation of realistic orbits and instrumental data all the way down to the retrieval of global gravity field solution time-series. Basic requirement for all these simulations are realistic representations of the spatio-temporal mass variability in the different sub-systems of the Earth, as a source model for the orbit computations. For such simulations, a suitable source model is required to represent (i) high-frequency (i.e., sub-daily to weekly) mass variability in the atmosphere and oceans, in order to realistically include the effects of temporal aliasing due to non-tidal high-frequency mass variability into the retrieved gravity fields. In parallel, (ii) low-frequency (i.e., monthly to interannual) variability needs to be modelled with realistic amplitudes, particularly at small spatial scales, in order to assess to what extent a new mission concept might provide further insight into physical processes currently not observable. The new source model documented here attempts to fulfil both requirements: Based on ECMWF’s recent atmospheric reanalysis ERA-Interim and corresponding simulations from numerical models of the other Earth system components, it offers spherical harmonic coefficients of the time-variable global gravity field due to mass variability in atmosphere, oceans, the terrestrial hydrosphere including the ice-sheets and glaciers, as well as the solid Earth. Simulated features range from sub-daily to multiyear periods with a spatial resolution of spherical harmonics degree and order 180 over a period of 12 years. In addition to the source model, a de-aliasing model for atmospheric and oceanic high-frequency variability with augmented systematic and random noise is required for a realistic simulation of the gravity field retrieval process, whose necessary error characteristics are discussed. The documentation is organized as follows: The characteristics of the updated ESM along with some basic validation are presented in Volume 1 of this report (Dobslaw et al., 2014). A detailed comparison to the original ESA ESM (Gruber et al., 2011) is provided in Volume 2 (Bergmann-Wolf et al., 2014), while Volume 3 (Forootan et al., 2014) contains a description of the strategy to derive a realistically noisy de-aliasing model for the high-frequency mass variability in atmosphere and oceans. The files of the updated ESA Earth System Model for gravity mission simulation studies are accessible at DOI:10.5880/GFZ.1.3.2014.001.

Description: Im Süden des italienischen Apennin befindet sich der Pollino-Gebirgszug. Als letztes Segment der ozeanischen Subduktion entlang der Nubisch-Eurasischen Platte dehnt sich das Gebiet unter einem komplexen System von Abschiebungen aus. Darin: Das Mercure-Becken und die Castrovillari-Störung, zusammen eine der prominentesten seismischen Lücken, dokumentiert durch den italienischen Erdbeben-Katalog. Jahrhundertelang wurde dort nie ein Erdbeben größer als Magnitude 6 verzeichnet. Während das Castrovillari-Gebiet weitestgehend aseismisch erscheint, wurde in den vergangenen Jahren das Mercure-Becken verstärkt von seismischen Schwärmen heimgesucht. Ein Verbundprojekt des GFZ mit dem Istituto Nazionale di Geofisica e Vulcanologia (INGV) stellt sich der Herausforderung, mehr über diese Schwarmbeben herauszufinden.

Description: The ratio of seismic P- to S-wave velocities (the Vp/Vs ratio) of a given rock volume is a sensitive proxy for the detection of fluids and melts. In subduction regimes it has often been inferred from seismic tomography and been used, e.g., to detect pathways of ascending melt above the seismogenic zone, where tomographic methods have their highest resolution. We present Vp/Vs ratios that were computed using only seismic arrival time observations following the approach of Lin and Shearer (2007). This approach has its highest sensitivity in the source volume of a set of nearby seismic events and is hence particularly well suited to directly probe the plate interface. We present data from a temporary local network of short period seismometers that was in operation in the forearc of the Central Andean subduction zone at 21 ◦ S between 2005 and 2012. From this database we were able to localize 3253 seismic events (Ml ∼ 0.5–4) with high precision, yielding a detailed image of the seismicity distribution in this region. Seismicity is pervasive within the entire crust of the South American continental plate and exhibits three distinct bands in the subducting slab, the lowermost one being located in the lithospheric mantle of the subducting plate. The highest concentration of seismic events is found in the contact zone between the continental and the oceanic lithosphere at depths between 30 and 50 km. We group seismic events into approximately 100 subsets of nearby events that origin from the same geo- logical structure. For about half of these subsets we are able to extract a reliable local Vp/Vs ratio. In the middle continental crust, Vp/Vs ratios show slightly enhanced values ( ∼ 1.75). In the lower continental crust towards the plate interface they tend to increase from this value updip and decrease downdip. At the plate interface itself, we observe higher Vp/Vs ratios (〉1.8) at shallower depths (between 20 and 40 km). Downdip (40–60 km depth) Vp/Vs ratios decrease to rather typical values ( ∼ 1.75). The same trend is observed in the lowermost band of mantle seismicity in the subducting slab. Below 80 km depth, where mineral transitions toward the eclogite facies are expected to occur, Vp/Vs ratios tend to be low (〈1.75). The consistently high Vp/Vs ratios in the shallow part of the subducting slab hint at the presence of fluids in the porespace of the subducting lithosphere there. In the deeper part, downdip variations of Vp/Vs may be attributed to mineral phase transitions due to the changing P-T-conditions along the subduction pathway.

Description: Die Publikationen der Mitarbeiter der seismologischen. Forschungseinrichtungen des Institutsteils Jena des Zentralinstituts für Physik der Erde und seiner Vorgängereinrichtungen Institut für Geodynamik, Jena Institut für Bodendynamik und Erdbebenforschung, Jena Zentralinstitut für Erdbebenforschung, Jena Reichsanstalt für Erdbebenforschung, Jena Hauptstation der Erdbebenforschung in Jena, die sie während ihrer Tätigkeit im Institut veröffentlichten, sind in einem chronologischen Hauptteil und einem Autorenregister für die Jahre 1922 - 1973 zusammengestellt.

Description: Zusammenfassung Vorwort Einleitung Chronologischer Teil Autorenregister

Description: The use of down-hole seismic instrumentation provides substantial benefits with regard to signal quality and reduced magnitude detection threshold in earthquake monitoring. This is mainly due to reduced levels of ambient and anthropogenic noise with depth, especially within the uppermost few hundred meters. Installing vertical arrays of seismometers in boreholes also allows including the depth as third dimension in addition to surface-based measurements. The installation procedure and selection of the depth of sensors in a borehole can range from quasi-permanent installations, with a retrieving option, to permanently cemented sensors in place. While sensor layouts generally depend on the boundary conditions of a specific project and are a compromise given the substantial drilling costs involved, the improvements in noise reduction generally open new windows in earthquake seismology and geomechanical reservoir monitoring. The current installation of highly sensitive down-hole seismometer arrays in monitoring wells around the eastern Sea of Marmara in Turkey (ICDP-GONAF project) and their integration into the local seismic network for monitoring the activity along the Princes Islands segment of the North Anatolian Fault Zone are discussed and first down-hole sensor responses are presented.

Description: Large coal deposits occur in South Africa. The production and use of these deposits enable South Africa to satisfy 70 % of its energy demand and 90 % of its electricity production utilising coal-fired power plants. However, coal combustion causes large carbon dioxide emissions, and South Africa – after signing the Kyoto protocol – strives towards reducing greenhouse gas emissions by 34 % by 2020. South Africa therefore looks to alternative energy resources, including renewables, but mainly centred on cleaner fossil energy carriers such as natural gas. Indeed, fossil fuels are high on the agenda, and exploration is ongoing both offshore and onshore. A major focus has recently developed on unconventional hydrocarbons on land in the Karoo Basin. Recent basic scientific findings have demonstrated that glacial events had a direct influence on the extent of black shale deposition in that basin. Within the framework of a long standing cooperation with South African academia and industry, a concerted effort has been made to better understand the present-day dynamics, structure and composition of the South African continental margins. Based on new 3D models, reconstructions of the margin evolution have assessed related processes as lithospheric stretching, heat flow through time and lateral variations of vertical movements. Such basic understanding is crucial for the understanding of offshore basins and their related oil and gas potential.

Description: This book is about management of arctic and northern alpine research stations. It has been produced by a group of station managers participating in the EU 7th Framework Programme Infrastructure project called INTERACT. With this book we want to share the knowledge and experiences we have gained from managing very different research stations in very different environmental and climatic settings. The target audience for the book is mainly managers of research stations in arctic and alpine areas, but we hope that it will also be useful for others involved in science coordination and logistics, e.g. research institutions, chief scientists and expedition planners. The book has been produced mainly based on input from practising station managers being part of ‘INTERACT Station Managers’ Forum (SMF), a forum established to provide a platform for exchange of information between station managers and other participants within INTERACT, and to collect and disseminate knowledge embedded within the network. The scope of this book is to identify and describe best practices and key considerations of relevance to station management under arctic and alpine conditions. As research stations operate under very different legal regimes, financial conditions, environmental and climatic conditions, as well as remoteness, it is not possible to identify specific best practices that fit all stations. Instead, we have described key issues that should be considered and addressed by station management, and supplemented this with examples of good practices from stations operating under different conditions (e.g. different climate, remoteness or size).

Description: Based on a 2 year seismic record from a local network, we characterize the deformation of the seismogenic crust of the Pamir in the northwestern part of the India‐Asia collision zone. We located more than 6000 upper crustal earthquakes in a regional 3‐D velocity model. For 132 of these events, we determined source mechanisms, mostly through full waveform moment tensor inversion of locally and regionally recorded seismograms. We also produced a new and comprehensive neotectonic map of the Pamir, which we relate to the seismic deformation. Along Pamir's northern margin, where GPS measurements show significant shortening, we find thrust and dextral strike‐slip faulting along west to northwest trending planes, indicating slip partitioning between northward thrusting and westward extrusion. An active, north‐northeast trending, sinistral transtensional fault system dissects the Pamir's interior, connecting the lakes Karakul and Sarez, and extends by distributed faulting into the Hindu Kush of Afghanistan. East of this lineament, the Pamir moves northward en bloc, showing little seismicity and internal deformation. The western Pamir exhibits a higher amount of seismic deformation; sinistral strike‐slip faulting on northeast trending or conjugate planes and normal faulting indicate east‐west extension and north‐south shortening. We explain this deformation pattern by the gravitational collapse of the western Pamir Plateau margin and the lateral extrusion of Pamir rocks into the Tajik‐Afghan depression, where it causes thin‐skinned shortening of basin sediments above an evaporitic décollement. Superposition of Pamir's bulk northward movement and collapse and westward extrusion of its western flank causes the gradual change of surface velocity orientations from north‐northwest to due west observed by GPS geodesy. The distributed shear deformation of the western Pamir and the activation of the Sarez‐Karakul fault system may ultimately be caused by the northeastward propagation of India's western transform margin into Asia, thereby linking deformation in the Pamir all the way to the Chaman fault in the south in Afghanistan.

Description: InnovaRig is a novel drill rig design with a wealth of innovative features for scientific drilling as well as industrial applications at highest standards of modern drilling technology. With its modular and containerized design it offers minimum turn-around time at reduced transportation logistics and a small environmental footprint, ideal for drilling locations in densely populated areas. Innovations have further been made in the areas of noise protection, energy saving and rig automation which reduces manpower as well as operational cost to a minimum. InnovaRig has already completed seven geothermal projects in sedimentary rocks in Germany and is currently planned to be mobilized to its first geothermal research drilling project in 5 km deep crystalline rocks.

Description: Dataset

Description: To obtain a precise record of the foreshock sequence before the 2014 Iquique, Chile Mw 8.1 earthquake, we applied a matched filter technique to continuous seismograms recorded near the source region. We newly detected about 10 times the number of seismic events listed in the routinely constructed earthquake catalog and identified multiple sequences of earthquake migrations at speeds of 2–10 km/d, both along strike and downdip on the fault plane, updip of the main shock area. In addition, we found out repeating earthquakes from the newly detected events, likely indicating aseismic slip along the plate boundary fault during the foreshock sequence. These observations suggest the occurrence of multiple slow-slip events updip of the main shock area. The final slow-slip event migrated toward the main shock nucleation point. We interpret that several parts of the plate boundary fault perhaps experienced slow slip, causing stress loading on the prospective largest slip patch of the main shock rupture.

Description: The scientific principles of reservoir engineering are a decisive key for an appropriate development of geothermal resources. Conventional geothermal resources cover a wide range of uses for power production and direct application. For unconventional systems a large scientific and industrial community has been involved in developing so-called Enhanced Geothermal Systems (EGS). The concept involves different ways to increase access to heat at depth by improving exploration methods, drilling and reservoir assessment technologies for deep geothermal resources, and ultimately the stimulation of low-permeability reservoirs. These stimulation treatments are a well established and well understood method with long experience in the oil and gas industry. They should be designed individually depending on the reservoir rock properties, stratigraphic sequences, and structural geological setting to achieve the best results in terms of developing an appropriate down hole heat exchanger and a strategy to reduce the risk of undesired seismic events. Designing a special concept of the well path, including sub horizontal sections in the reservoir and special alignment according to the stress field, offers the possibility for multiple fracture treatments in a well to develop the geothermal field. In case of generating mostly tensile fractures with minor shear displacement, sustainability of fracture opening can be assured by adding proppants (meshed sand or man-made ceramics). A cyclic injection design in combination with the multi-frac concept tends to produce less seismic events with significant lower total seismic energy release if compared to a constant flow rate and a single fracture treatment.

Description: Two devastating earthquakes with moment magnitudes of 7.2 and 5.6 occurred on October 23, 2011 (Van-Erciş earthquake) and November 9, 2011 (Van-Edremit earthquake), respectively, in the Van Province of the eastern Turkey. The Van-Erciş and Van-Edremit earthquakes caused 604 and 38 fatalities, respectively, and heavy damage to buildings and other structures, particularly in Erciş town and Van City. In this study, characteristics of both main shocks and their geotechnical aspects, such as local site conditions, liquefaction phenomena and associated ground deformations and slope failures are evaluated. The failures of slopes and embankments and rock falls and ground liquefaction may also be indications of diluted ground deformation caused by the earthquake fault. It seems that a wedge-like body bounded by two fault planes was uplifted. As a result of this movement, the northern shoreline of Van Lake uplifted. The November 9, 2011 Van-Edremit earthquake was triggered due to the variation of crustal stresses induced by the October 23, 2011 earthquake. The effects of local site conditions have contributed to the damage of some parts of Erciş city and its vicinity; however, the ground liquefaction was not observed in the city as anticipated. With a magnitude of 5.6, the Van-Edremit earthquake is probably the smallest magnitude earthquake to cause liquefaction in Turkey so far.

Description: Paleozoic siliciclastic rocks from the Schwarzburg area of the German Saxo-Thuringian Zone encompass a 250 Ma peri-Gondwanan sedimentary record from the Cadomian to the Variscan orogenies. The sediments were deposited in environments that changed through time from terrestrial to shallow marine, deep marine, and eventually with the onset of the Variscan orogeny back to shallow marine and terrestrial again. Even for rocks of only minor major-element variability, the isotopic compositions of Li and B may encompass a range of more than 20 δ-units, depending on the weathering history of their source, the environment of deposition (terrestrial, lacustrine, marine), and post-depositional alteration. In particular, the relative contributions of structure-bound and exchangeable Li and B has a major effect on the isotopic composition of the bulk sample and may result in a decoupling of the Li and B isotopic compositions in sedimentary rocks. The Li isotopic composition shows little variation, except for deeply weathered Permian shales that were deposited in a terrestrial environment (slightly lower δ7Li values) and deeply weathered early Ordovician deposits that have been redeposited in a marine environment and have very high δ7Li values due to high contributions of exchangeable Li. The B isotopic composition shows for early Paleozoic sedimentary rocks a systematic increase in δ11B from − 24.0‰ to − 4.2‰ that in part reflects the change from terrestrial to open marine deposition and in part is due to mineralogical variation. The δ11B values of post-Hirnantian (late Ordovician) sedimentary rocks range from − 15‰ to − 5.2‰. There is no significant effect of the sediment source or protolith nature on the Li isotopic composition of the siliciclastic sedimentary rocks. Instead, major variations in the Li and B isotopic composition are controlled by depositional environment (terrestrial vs. marine) as the content of exchangeable Li and B is mineralogically controlled. The highest δ7Li and δ11B values are found in marine illite-rich samples and marine chlorite-rich samples, respectively.

Description: The present number contains the papers read at the conference "Statistical and Tectonophysical Aspects of Seismicity" held from May 16 to 18, 1972, at the Central Earth Physics Institute of the German Academy of Sciences of Berlin, Jena branch, which serve as a basis for the discussions of the working group “Statistical Methods" within the subcommission "Seismicity of Europa" of the European Seismological Commission. In his opening speech the Director of the institute, Prof. STILLER, pointed out the importance of quantitative representation of seismicity for the complex problems of the project of geodynamics. The chairman of the European Seismological Commission, Prof. SAVARENSKY, Moscow, emphasized the statistical aspects of seismicity and explained the potentialities of physical interpretation of the laws established as well as their application to estimating the earthquake risk under various aspects. SCHENKOVÁ analysed the chronological succession of the earthquake of the northeastern Mediterranean in the period (1901, 1967) in the light of several models, from which an optimum model was found by the x²-test. PURCARU examined models of the frequency-magnitude dependence, e.g. those of UTSU and of OKADA, from the view-point of information theory. In two papers read by PANZA the seismicity of Italy including the fundamentals of representation was discussed, where the GUTENBERG-RICHTER magnitude-frequency relation is the underlying principle. Its coefficients were determined for the various seismotectonic units of Italy. Moreover, models of intensity distribution about the epicentres were set up for these regions. On the basis of seismic data going back as far as to the Birth of Christ maps of the seismic risk and of the active faults were then drawn up. Furthermore, PANZA demonstrated the great dependence of the magnitude value as obtained from the seismic surface waves on the focus depth of an earthquake in the earth's crust. MAAZ and PURCARU as well as NEUNHÖFER and MAAZ were concerned with logarithmically normal distributions of the frequency of earthquakes over the magnitude or energy, the determination of their coefficients and their confidence intervals. PROCHÁZKOVÁ pointed out the necessity of standardized methods for determining the parameters of the GUTENBERG-RICHTER frequency-magnitude distribution and gave recommendations in this respect. Two papers by ULLMANN and MAAZ established the connection of the seismicity function as energy flow density with the energy distribution in the focus by means of the BÅTH-DUDA formula for focus volumes and rendered a generalization of the seismicity function in which the inaccuracy of the focus coordinates is statistically considered.

Description: The coherent behavior of four parameters characterizing the global field of low-frequency (periods from 2 to 500 min) seismic noise is studied. These parameters include logarithmic variance, kurtosis (coefficient of excess), width of support of multifractal singularity spectrum, and minimal normalized entropy of the distribution of the squared orthogonal wavelet coefficients. The analy)sis is based on the data from 229 broadband stations of GSN, GEOSCOPE, and GEOFON networks for a 16-year period from the beginning of 1997 to the end of 2012. The entire set of stations is subdivided into eight groups, which, taken together, provide full coverage of the Earth. The daily median values of the studied noise parameters are calculated in each group. This procedure yields four 8-dimensional time series with a time step of 1 day with a length of 5844 samples in each scalar component. For each of the four 8-dimensional time series, the frequency-time diagram of the evolution of the spectral measure of coherence (based on canonical coherences) is constructed in the moving time window with a length of 365 days. Besides, for each parameter, the maximum-frequency values of the coherence measure and their mean over the four analyzed noise parameters are calculated as a measure of synchronization that depends on time only. Based on the conducted analysis, it is concluded that the increase in the intensity of the strongest (M ≥ 8.5) earthquakes after the mega-earthquake on Sumatra on December 26, 2004 was preceded by the enhancement of synchronization between the parameters of global seismic noise over the entire time interval of observations since the beginning of 1997. This synchronization continues growing up to the end of the studied period (2012), which can be interpreted as a probable precursor of the further increase in the intensity of the strongest earthquakes all over the world.

Description: We present results from microseismic monitoring and geomechanical analysis obtained at the industrial-scale CO2 sequestration site at the In Salah gas development project in Algeria. More than 5000 microseismic events have been detected at a pilot monitoring well using a master event cross-correlation method. The microseismic activity occurs in four distinct clusters and thereof three clearly correlate with injection rates and wellhead pressures. These event clusters are consistent with a location within the reservoir interval. However, due to insufficient network geometry there are large uncertainties on event location. We estimate a fracture pressure of 155 bar (at the wellhead) from the comparison of injection pressure and injection rate and conclude that reservoir fracture pressure of the injection horizon has most likely been exceeded occasionally, accompanied by increased microseismic activity. Our analysis of 3-D ray tracing for direct and converted phases suggests that one of the event clusters is located at a shallower depth than the reservoir injection interval. However, this event cluster is most likely unrelated to changes in the injection activity at a single well, as the event times do not correlate with the wellhead pressures. Furthermore, this event cluster shows b-values close to one, indicating re-activated natural or tectonic seismicity on pre-existing weakness zones rather than injection induced seismicity. Analysis of event azimuths and significant shear wave splitting of up to 5 per cent provide further valuable insight into fluid migration and fracture orientation at the reservoir level. Although only one geophone was available during the critical injection period, the microseismic monitoring of CO2 injection at In Salah is capable of addressing some of the most relevant questions about fluid migration and reservoir integrity. An improved monitoring array with larger aperture and higher sensitivity is highly recommended, as it could greatly enhance the value of this technique. As such, real-time microseismic monitoring can be used to guide the injection pressure below fracture pressure, thus providing a tool to mitigate the risk of inducing felt seismicity and compromising seal integrity.

Description: In this study, SKS and local S phases are analyzed to investigate variations of shear-wave splitting parameters along two dense seismic profiles across the central Andean Altiplano and Puna plateaus. In contrast to previous observations, the vast majority of the measurements reveal fast polarizations sub-parallel to the subduction direction of the Nazca plate with delay times between 0.3 and 1.2 s. Local phases show larger variations of fast polarizations and exhibit delay times ranging between 0.1 and 1.1 s. Two 70 km and 100 km wide sections along the Altiplano profile exhibit larger delay times and are characterized by fast polarizations oriented sub-parallel to major fault zones. Based on finite-difference wavefield calculations for anisotropic subduction zone models we demonstrate that the observations are best explained by fossil slab anisotropy with fast symmetry axes oriented sub-parallel to the slab movement in combination with a significant component of crustal anisotropy of nearly trench-parallel fast-axis orientation. From the modeling we exclude a sub-lithospheric origin of the observed strong anomalies due to the short-scale variations of the fast polarizations. Instead, our results indicate that anisotropy in the Central Andes generally reflects the direction of plate motion while the observed trench-parallel fast polarizations likely originate in the continental crust above the subducting slab.

Description: Beneath the Pamir and Hindu Kush mountains an earthquake zone is observed in 80 to 300 km depth. It resembles in form and intensity the intermediate depth seismicity in subduction zones, here lithosphere is recycled in the Earth’s mantle. The fundamental tectonic concept of subduction is well established for convergent margins including an oceanic plate. The Pamir, however, is situated in an intra-continental setting and is formed during a continent-continent collision. This thesis aims to contribute to the investigation of the active tectonic process underlying the local occurrence of the seismicity in upper mantle depths. The field experiment for this study was performed in the framework of the multidisciplinary TIPAGE project from 2008 to 2010 and included large parts of the Pamir, the adjacent Tajik Depression and the Southern Tien Shan. The receiver function technique was applied to detect and locate seismic discontinuities in the subsurface in order to perform seismic imaging. The results clearly attest to an intra-continental subduction. Beneath the Pamir, the subducting plate is of Eurasian provenance. A southerly dipping 10 to 15 km thick low velocity zone could be resolved along a north-south profile in the eastern Pamir framing the earthquake zone in the upper mantle. This low velocity zone appears to be connected to the lower crust north of the seismic zone indicating subduction of crustal material in north to south direction. West of this north-south profile the zone of intermediate depth seismicity describes an arc changing its strike from east-west beneath the eastern Pamir to north-south beneath the western Pamir. Thereby the dipping direction of the slab changes from due south to due east. The geometry of this slab is confirmed by various receiver function cross sections. Towards western direction the subducted slab is connected to the crust of the Tajik Depression, indicating that the slab is the western extension of the Tajik Depression plate. Since the crustal thickness of the Tajik Depression is determined to at least 40 km, a continental composition for the crust of the Tajik Depression is inferred even though its underlying mantle lithosphere appears to be thin. The crustal thickness is mapped for the whole region. The resulting Moho map shows a 65 to 75 km thick crust in the Pamir and a 40 to 45 km thick crust in the surrounding basins. The arcuate subduction of the Tajik Depression plate and its eastern extension is reflected by characteristic Moho depth anomalies along the arc.

Description: The problem of monitoring of different types of seismic events – geoacoustic precursors of earthquakes, industrial and field explosions, places fragments fall of separating parts of rockets-carriers, etc. is one of the key in the modern ecology of the environment. The peculiarity of this kind of monitoring is that it is mobile seismic groups, which should be based in the proposed area of occurrence of events. One of the most important steps for solving the problems connected with the detection and identification of recorded data from passive sensors in mobile seismic array (MSA). The task of determining the nature of the source and its' coordinates lies in the basis of direction, referred to as the geoacoustic location. Using a new approach (not by location but by neural classification of waveform "portraits") usability of algorithm which based on quantitative parameters of signal will be demonstrated.

Description: After more than 4.5 years in orbit, the Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission ended with the reentry of the satellite on 11 November 2013. This publication serves as a reference for the fifth gravity field model based on the time-wise approach (EGM_TIM_RL05), a global model only determined from GOCE observations. Due to its independence of any other gravity data, a consistent and homogeneous set of spherical harmonic coefficients up to degree and order 280 (corresponding to spatial resolution of 71.5km on ground) is provided including a full covariance matrix characterizing the uncertainties of the model. The associated covariance matrix realistically describes the model quality. It is the first model which is purely based on GOCE including all observations collected during the entire mission. The achieved mean global accuracy is 2.4cm in terms of geoid heights and 0.7mGal for gravity anomalies at a spatial resolution of 100km.

Description: Southern Africa was part of Gondwanaland until the Mesozoic, when this supercontinent broke up into fragments that evolved into today’s southern continents. In particular, around 140 Ma, rifting started between southern Africa and South America, followed by the opening of the South Atlantic after ~130 Ma. What caused this breakup is a subject of ongoing research. In particular, it is unclear whether, and to what extent, plumes from the deep mantle are a cause for, or at least assisted in the breakup, or whether, on the contrary, the flood basalt provinces attributed to plumes are a consequence of breakup. The Paraná and Etendeka flood basalts erupted ~132 Ma ago at a location nearly vertically above the margin of the African “Large Low Shear Velocity Province” in the lowermost mantle, indicative of a deep mantle plume. Plate reconstructions show that the plume was initially beneath the South American plate, but close to the breakup location, such that plume material could flow to and erupt at the developing spreading ridge. The plume was overridden by the ridge at ~90 Ma and has been under the African plate ever since. Plume-lithosphere interaction can also be addressed through active seismic surveys on land, and in combination with petrologic and geochemical studies of the flood basalts and dyke swarms, this work has led to many important new insights. In particular, it has been shown that mantle temperatures beneath Etendeka province were about 150 °C higher than the global mid-oceanic ridge average, thus further supporting the mantle plume hypothesis.

Description: The Cyprean arc is considered to be a convergent boundary in the Eastern Mediterranean where the African plate is being subducted beneath the Anatolian plate. Mapping the lateral variations of seismic anisotropy parameters can provide essential hints to mantle dynamics and flow patterns in relation to the geometry and style of deformation developed under different pressure, temperature conditions around the subducting African lithosphere. In this study, seismic anisotropy parameters, fast polarization directions (ϕ) and delay times (δt) beneath the Cyprean arc and NE Mediterranean Sea are inferred from the shear wave splitting analysis performed on core-mantle refracted teleseismic shear waves (SKS phases). Earthquake data used in the present work are extracted from the continuous recordings of 8 broad-band seismic stations located in the study region for a time period during 1999 and 2012. The overall results exhibits clear evidences of mantle anisotropy with relatively uniform NE–SW aligned fast polarization directions. No abrupt changes in fast polarization directions (ϕ) are observed. However, near the Dead Sea Transform Fault, ϕ values tend to rotate from NE–SW to N–S and NW–SE in accordance with Pn anisotropy observations. Delay times (δt) vary between 0.61 s ± 0.10 s and 1.90 s ± 0.13 s. The range of delay times are generally consistent with those observed in the mantle rather than implying a crustal anisotropy. A predominant pattern of NNE–SSW fast polarization directions that is coherent with earlier SKS splitting measurements observed beneath north, central and East Anatolia suggests a SW directed asthenospheric flow caused by slab rollback process along the Hellenic and Cyprean arcs. Furthermore, apparent splitting parameters did not exhibit any significant directional dependence which may imply possibility of the presence of anisotropic models with two-layer anisotropy or dipping axis of symmetry beneath the northeast Mediterranean Sea and Cyprean arc. Consequently, a simple, single-layered and sub-horizontal anisotropy model is tentatively suggested for the study region.

Description: We study acoustic emissions (AEs) associated with shear and tensile failures around a horizontal borehole in a sandstone sample subjected to triaxial stress. The aim is to relate the AE event rate to macroscopic observations of sample deformation and the percentage of isotropic and deviatoric components of the seismic moment tensors to the expected failure mechanisms. The horizontal hole interferes with the applied load and forms a strongly spatially dependent anisotropic stress field, focusing the crack initiation into both shear and tensile failures. The recorded AEs follows reasonably well existing damage models, but the elastic solution of hoop stress does not represent the onset of failure around the borehole. The focal mechanisms correlate with the orientation of macroscopic fractures in the sample. Events close to the borehole show a higher fraction of isotropic percentage in moment tensors compared to events occurring in the macroscopic fracture featuring higher double-couple percentages. The inhomogeneous stress field due to the borehole and the stress induced damage is strongly affecting the axial and radial velocities which in turn affect the waveforms of the recorded AEs and the resulting moment tensors. The VP/VS ratio obtained from the ratio of isotropic to compensated linear vector dipole components of the moment tensors is close to that obtained from ultrasonic velocity measurements.

Description: The Tarutung Basin is located at a right step-over in the northern central segment of the dextral strike-slip Sumatran Fault System (SFS). Details of the fault structure along the Tarutung Basin are derived from the relocations of seismicity as well as from focal mechanism and structural geology. The seismicity distribution derived by a 3D inversion for hypocenter relocation is clustered according to a fault-like seismicity distribution. The seismicity is relocated with a double-difference technique (HYPODD) involving the waveform cross-correlations. We used 46,904 and 3191 arrival differences obtained from catalogue data and cross-correlation analysis, respectively. Focal mechanisms of events were analyzed by applying a grid search method (HASH code). Although there is no significant shift of the hypocenters (10.8 m in average) and centroids (167 m in average), the application of the double difference relocation sharpens the earthquake distribution. The earthquake lineation reflects the fault system, the extensional duplex fault system, and the negative flower structure within the Tarutung Basin. The focal mechanisms of events at the edge of the basin are dominantly of strike-slip type representing the dextral strike-slip Sumatran Fault System. The almost north–south striking normal fault events along extensional zones beneath the basin correlate with the maximum principal stress direction which is the direction of the Indo-Australian plate motion. The extensional zones form an en-echelon pattern indicated by the presence of strike-slip faults striking NE–SW to NW–SE events. The detailed characteristics of the fault system derived from the seismological study are also corroborated by structural geology at the surface.

Description: Die Eismassendynamik in der Arktis ist eine Schlüsselgröße im globalen Klimageschehen. Seismische Beobachtungen können hier Satelliten-, Eisradar- und GPS-Beobachtungen in entscheidender Weise ergänzen.

Description: Die lithologische Beschreibung und Bestandsaufnahme sedimentärer Schichtfolgen erfordert eine organisierte Dokumentationsform, besonders wenn umfangreiches Bohrkernmaterial ausgewertet werden soll und lithologische Daten zur Archivierung vorgesehen sind. Dafür eignen sich Dokumentationstabellen, in denen verbale Beschreibungen fast ausschließlich auf Zeichen oder Symbole reduziert sind. Tabellarische Dokumentation erfordert die Berücksichtigung allgemeiner Fragen der Klassifikation und Skalierung von Merkmalen. Es werden drei Arbeitstabellen vorgelegt, die sich im Grad der Ausführlichkeit unterscheiden und vorrangig für klastische Sedimente mit geringen Einlagerungen anderer Sedimentgesteine verwendet werden können.

Description: 1. Einleitung 2. Allgemeine Grundlagen lithologischer Dokumentation 2.1. Intensität der Dokumentation 2.2. Merkmalsklassifikation 2.3. Skalierungsfragen 3. Tabellarische Dokumentation 3.1. Aufbau der Tabellen 3.2. Stratifizierungsprobleme 3.3. Vor- und Nachteile der tabellarischen Dokumentation 3.4. Anwendungsbereich und Weiterverarbeitung 4. Tabelle zur Dokumentation klastischer Sedimente (ausführliche Variante) 4.1. Übergeordnete Einheiten 4.2. Koordinaten 4.2.1. Laufende Nummer 4.2.2. Teufenangaben 4.2.3. Mächtigkeit 4.3. Teilkörperanteil 4.4. Stoffbestand 4.4.1. Gerüstbildende Komponente 4.4.2. Einzelkomponenten. 4.4.3. Fossilien 4.5. Gefüge 4.5.1. Korngefüge 4.5.1.1. Korngröße 4.5.1.2. Klastengefüge 4.5.1.2.1. Bestandteil 4.5.1.2.2. Rundung 4.5.1.2.3. Packung 4.5.1.2.4. Anordnung 4.5.1.3. Gefüge chemogener Bestandteile 4.5.1.3.1. Blasten 4.5.1.3.2. Konkretionen 4.5.1.3.3. Zement 4.5.2. Schichtgefüge 4.5.2.1. Horizontalschichtung 4.5.2.1.1. Wechsellagerung 4.5.2.1.2. Lamination 4.5.2.1.3. Gradierung 4.5.2.2. Schrägschichtung 4.5.2.3. Merkmale auf Schichtflächen 4.5.2.4. DeformationenUntergrenze 4.5.3. Tektonische Gefüge 4.5.3.1. Schichtfallen 4.5.3.2. Klüftung 4.6. Masseneigenschaften 4.6.1. Porosität 4.6.2. Festigkeit 4.6.3. Farbe 4.7. Gesteinstyp 4.8. Dokumentationstechnische Angaben 4.8.1. Kernbeschaffenheit 4.8.2. Proben 4.9. Bemerkungen 4.10. Dokumentationsbeispiel 5. Vereinfachte Tabellenvarianten 5.1. Variante 2: Tabelle zur Felddokumentation (Feld-Dok-Tabelle) 5.2. Variante 3: Tabelle zur Kurzdokumentation (Kurz-Dok-Tabelle) 6. Zusammenfassung der Ergebnisse 7. Literatur Tabular documentation of clastic sediments Sachregister