ALBERT

Description: This study combined data on fin whale Balaenoptera physalus, humpback whale Megaptera novaeangliae, minke whale B. acutorostrata, and sei whale B. borealis sightings from large-scale visual aerial and ship-based surveys (248 and 157 sightings, respectively) with synoptic acoustic sampling of krill Meganyctiphanes norvegica and Thysanoessa sp. abundance in September 2005 in West Greenland to examine the relationships between whales and their prey. Krill densities were obtained by converting relationships of volume backscattering strengths at multiple frequencies to a numerical density using an estimate of krill target strength. Krill data were vertically integrated in 25 m depth bins between 0 and 300 m to obtain water column biomass (g/m**2) and translated to density surfaces using ordinary kriging. Standard regression models (Generalized Additive Modeling, GAM, and Generalized Linear Modeling, GLM) were developed to identify important explanatory variables relating the presence, absence, and density of large whales to the physical and biological environment and different survey platforms. Large baleen whales were concentrated in 3 focal areas: (1) the northern edge of Lille Hellefiske bank between 65 and 67°N, (2) north of Paamiut at 63°N, and (3) in South Greenland between 60 and 61° N. There was a bimodal pattern of mean krill density between depths, with one peak between 50 and 75 m (mean 0.75 g/m**2, SD 2.74) and another between 225 and 275 m (mean 1.2 to 1.3 g/m**2, SD 23 to 19). Water column krill biomass was 3 times higher in South Greenland than at any other site along the coast. Total depth-integrated krill biomass was 1.3 x 10**9 (CV 0.11). Models indicated the most important parameter in predicting large baleen whale presence was integrated krill abundance, although this relationship was only significant for sightings obtained on the ship survey. This suggests that a high degree of spatio-temporal synchrony in observations is necessary for quantifying predator-prey relationships. Krill biomass was most predictive of whale presence at depths 〉150 m, suggesting a threshold depth below which it is energetically optimal for baleen whales to forage on krill in West Greenland.

Description: We present paleomagnetic and mineral magnetic results from ocean sediments from the southern Okinawa Trough (west Pacific). We obtained samples from two holes from Ocean Drilling Program Site 1202 and determined the natural remanent magnetization, magnetic susceptibility, anhysteretic remanent magnetization (ARM), hysteresis properties, and thermomagnetic behavior. Hole 1202A was studied between 100 and 120 meters below seafloor (mbsf) and Hole 1202B between 0 and 140 mbsf, both at 1-cm resolution. Hysteresis properties and thermomagnetic behavior were measured on selected samples. The measurements show a stable magnetization carried by pseudo-single-domain-sized low-titanium magnetite. Magnetic inclinations are predominantly positive and record the Brunhes (C1n) normal polarity chron. Susceptibility and ARM, as well as the environmentally significant rock magnetic ratios (ARM/k and ARM30 mT/ARM0 mT), reflect changes in sediment input from Taiwan and the East China Sea continental shelf changes in the path of the Kuroshio Current and changes in climatic conditions.

Description: The Gulf of Carpentaria is an epicontinental sea (maximum depth 70 m) between Australia and New Guinea, bordered to the east by Torres Strait (currently 12 m deep) and to the west by the Arafura Sill (53 m below present sea level). Throughout the Quaternary, during times of low sea-level, the Gulf was separated from the open waters of the Indian and Pacific Oceans, forming Lake Carpentaria, an isolation basin, perched above contemporaneous sea-level with outlet channels to the Arafura Sea. A preliminary interpretation is presented of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria. The longest core (approx. 15 m) spans the past 130 ka and includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 ka when sea-level repeatedly breached and withdrew from Gulf/Lake Carpentaria. Evidence from biotic remains (foraminifers, ostracods, pollen), sedimentology and geochemistry clearly identifies a final marine transgression at about 9.7 ka (radiocarbon years). Before this transgression, Lake Carpentaria was surrounded by grassland, was near full, and may have had a surface area approaching 600 km-300 km and a depth of about 15 m. The earlier rise in sea-level which accompanied the Marine Isotopic Stage 6/5 transgression at about 130 ka is constrained by sedimentological and biotic evidence and dated by optical- and thermoluminescence and amino acid racemisation methods.

Description: We provide a database of the coseismic surface ruptures produced by the 21 August 2017 Md 4.0 earthquake that struck the Casamicciola Terme village in the north of Ischia volcanic island (Italy). Despite its small size, the earthquake caused two fatalities and heavy damages in a restricted area of a few square kilometers. The shallow hypocentral depth of the earthquake caused a significant coseismic surface faulting, testified by a main alignment of ruptures mapped for a 2 km end-to-end length along the Casamicciola E-W trending normal fault system, bounding the northern slope of Mt. Epomeo. Casamicciola Terme has been recurrently destroyed in the last centuries by similar volcano-tectonic earthquakes (1762, 1767, 1796, 1828, 1881, and 1883). After the catastrophic 1883 Casamicciola event (2343 casualties), this is the first heavy damaging earthquake at Ischia that provides, for the first time, the opportunity of integrating historical seismicity, macroseismic observations, instrumental information, and detailed mapping of coseismic geological effects. We performed a detailed field surveys in the epicentral region of the 21 August earthquake to describe the ruptures geometry and kinematics of the seismogenetic fault responsible of the earthquake with the aim of contributing to the seismic hazard evaluation and land use planning in the Ischia island, one of the most crowded touristic destinations worldwide. Summarizing our study of ground effects for the 21 August 2017 earthquake is important for improving knowledge on surface earthquake in the volcanic area and contributing to complete the gap of empirical scaling relating to the surface-faulting mechanism due to small-size or moderate earthquakes in volcano-tectonic framework. The collected field observations result in a dataset of 88 georeferenced records describing coseismic ruptures/fractures by features as ID number, time of sample collection, location (latitude, longitude, elevation), type of rupture, type of affected substratum, attitude (dip angle, dip direction, strike), surface offset (opening, throw, strike slip, net slip), kinematics, slip vector attitude, width of the deformation zone.

Description: Selected multicorer cores of R/V Sonne cruise SO268-1 and were scanned by a Toshiba Aquilion 64 computer tomograph (CT) at the hospital Klinikum Bremen-Mitte with an x-ray source voltage of 120 kV and a current of 600 mA. The CT image stacks have a resolution of 0.35 mm in x/y-direction and 0.5 mm resolution in z-direction (0.3 mm reconstruction unit). Images were reconstructed using Toshiba's patented helical cone beam reconstruction technique (TCOT) and are provided in DICOM-format. The data were processed with the ZIB edition of the Amira software (version 2021.03; Stalling et al., 2005; http://amira.zib.de). Within Amira, the core liners, including about 2 mm of the core rims, were deleted from the data set. Mangan nodules with diameters 〉1 mm, open bioturbation traces, an unidentified organism (only present in core SO268-2-200-1 MC18), the natural bioturbated and surficial homogenised sediment were segmented by a marker-based watershed segmentation and visualized in 3D. Subsequently, the sediment components were quantified (MaterialStatistics module; volume per slice) and the mean and standard deviation of the sediment x-ray attenuation (MaterialStatistics module; statistics per slice per label; to avoid marginal averaging effects the sediment label was reduced by three voxels) were determined.

Description: Oxygen isotopes in biogenic silica (δ18O BSi) from lake sediments allow for quantitative reconstruction of past hydroclimate and proxy–model comparison in terrestrial environments. The signals of individual records have been attributed to different factors, such as air temperature (T air ), atmospheric circulation patterns, hydrological changes and lake evaporation. Here, we provide 55 composite down–core records published to date and complemented with additional lake basin parameters (e.g. lake water residence time and catchment size) to best characterize the signal properties. Records feature widely different temporal coverage and resolution ranging from decadal–scale records covering the last 150 years to records with multi–millennial scale resolution spanning glacial–interglacial cycles. Best coverage in number of records (N=37) and datapoints (N=2112) is available for northern hemispheric (NH) extra–tropic regions throughout the Holocene (corresponding to Marine Isotope Stage 1; MIS 1).

Description: We provide a database of the coseismic surface ruptures produced by the 26 December 2018 Mw 4.9 earthquake that struck the eastern flank of Mt. Etna (southern Italy), the largest active volcano in Europe. Despite its small size, this shallow earthquake caused an impressive system of coseismic surface ruptures extending about 8.5 km, along the trace of the NNW-trending active Fiandaca Fault. We performed detailed field surveys were performed in the epicentral region to describe the ruptures geometry and kinematics. These exhibit a dominant right-oblique sense of slip with coseismic displacement peaks of 0.35 m. The Fiandaca Fault is part of a complex active faults system affecting the eastern flank of Mt. Etna. Its seismic history indicates a prominent surface-faulting potential, so our study is essential for unravelling the seismotectonics of shallow earthquakes in volcanic settings, and contributes updating empirical scaling laws relating moderate-sized earthquakes and surface faulting. The collected observations have been parsed and organized in a concise database consisting of 874 homogeneous georeferenced records. The main features describing the coseismic ruptures are the following: ID, time of sample collection, location (latitude, longitude, elevation), type of rupture, type of affected substratum, attitude (dip angle, dip direction, strike), surface offset (opening, throw, strike slip, net slip), kinematics, slip vector attitude, width of the deformation zone.

Description: Selected multicorer cores of R/V Sonne cruise SO268-1 and were scanned by a Toshiba Aquilion 64 computer tomograph (CT) at the hospital Klinikum Bremen-Mitte with an x-ray source voltage of 120 kV and a current of 600 mA. The CT image stacks have a resolution of 0.35 mm in x/y-direction and 0.5 mm resolution in z-direction (0.3 mm reconstruction unit). Images were reconstructed using Toshiba's patented helical cone beam reconstruction technique (TCOT) and are provided in DICOM-format. The data were processed with the ZIB edition of the Amira software (version 2021.03; Stalling et al., 2005; http://amira.zib.de). Within Amira, the core liners, including about 2 mm of the core rims, were deleted from the data set. Mangan nodules with diameters 〉1 mm, open bioturbation traces, an unidentified organism (only present in core SO268-2-200-1 MC18), the natural bioturbated and surficial homogenised sediment were segmented by a marker-based watershed segmentation and visualized in 3D. Subsequently, the sediment components were quantified (MaterialStatistics module; volume per slice) and the mean and standard deviation of the sediment x-ray attenuation (MaterialStatistics module; statistics per slice per label; to avoid marginal averaging effects the sediment label was reduced by three voxels) were determined.

Description: Selected multicorer cores of R/V Sonne cruise SO268-1 and were scanned by a Toshiba Aquilion 64 computer tomograph (CT) at the hospital Klinikum Bremen-Mitte with an x-ray source voltage of 120 kV and a current of 600 mA. The CT image stacks have a resolution of 0.35 mm in x/y-direction and 0.5 mm resolution in z-direction (0.3 mm reconstruction unit). Images were reconstructed using Toshiba's patented helical cone beam reconstruction technique (TCOT) and are provided in DICOM-format. The data were processed with the ZIB edition of the Amira software (version 2021.03; Stalling et al., 2005; http://amira.zib.de). Within Amira, the core liners, including about 2 mm of the core rims, were deleted from the data set. Mangan nodules with diameters 〉1 mm, open bioturbation traces, an unidentified organism (only present in core SO268-2-200-1 MC18), the natural bioturbated and surficial homogenised sediment were segmented by a marker-based watershed segmentation and visualized in 3D. Subsequently, the sediment components were quantified (MaterialStatistics module; volume per slice) and the mean and standard deviation of the sediment x-ray attenuation (MaterialStatistics module; statistics per slice per label; to avoid marginal averaging effects the sediment label was reduced by three voxels) were determined.

Description: Selected multicorer cores of R/V Sonne cruise SO268-1 and were scanned by a Toshiba Aquilion 64 computer tomograph (CT) at the hospital Klinikum Bremen-Mitte with an x-ray source voltage of 120 kV and a current of 600 mA. The CT image stacks have a resolution of 0.35 mm in x/y-direction and 0.5 mm resolution in z-direction (0.3 mm reconstruction unit). Images were reconstructed using Toshiba's patented helical cone beam reconstruction technique (TCOT) and are provided in DICOM-format. The data were processed with the ZIB edition of the Amira software (version 2021.03; Stalling et al., 2005; http://amira.zib.de). Within Amira, the core liners, including about 2 mm of the core rims, were deleted from the data set. Mangan nodules with diameters 〉1 mm, open bioturbation traces, an unidentified organism (only present in core SO268-2-200-1 MC18), the natural bioturbated and surficial homogenised sediment were segmented by a marker-based watershed segmentation and visualized in 3D. Subsequently, the sediment components were quantified (MaterialStatistics module; volume per slice) and the mean and standard deviation of the sediment x-ray attenuation (MaterialStatistics module; statistics per slice per label; to avoid marginal averaging effects the sediment label was reduced by three voxels) were determined.