cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5880/fidgeo.2022.001
title: Material properties of analogue velocity-weakening material used for seismotectonic analogue modeling of strike-slip seismic cycle: the case of twice-broken rice

description: This dataset provides friction data from ring-shear tests (RST) on twice broken rice used in the GEC Laboratory in CY Cergy Paris University in stick-slip experiments. They were obtained by Sarah Visage as part of her doctoral training (funded by the ANR DISRUPT programme) during an invitation at the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam. Like any granular material, the twice broken rice is characterized by several internal friction coefficients μ and cohesions C, classicaly qualified as dynamic, static, and reactivation coefficients. In adition, since the rice exhibits a stick slip behaviour, the various shear - velocity or shear-displacement curves exhibit high frequency oscillations and we therefore define maximum, minimum, and mean values corresponding respectively to the curve peaks, curve troughs and smoothed curve.
DOI: 10.5880/fidgeo.2022.004
title: VOLcanic conduit processes and their effect on PROjectile eXit dYnamics (VOLPROXY)

description: Volcanic projectiles are centimeter- to meter-sized clasts – both solid-to-molten rock fragments or lithic eroded from conduits – ejected during explosive volcanic eruptions that follow ballistic trajectories. Despite being ranked as less dangerous than large-scale processes such as pyroclastic density currents (hot avalanches of gas and pyroclasts), volcanic projectiles still represent a constant threat to life and properties in the vicinity of volcanic vents, and frequently cause fatal accidents on volcanoes. Mapping of their size, shape, and location in volcanic deposits can be combined to model possible trajectories of projectiles from the vent to their final position, and to estimate crucial source parameters of the driving eruption, such as ejection velocity and pressure differential at the vent. Moreover, size and spatial distributions of volcanic projectiles from past eruptions, coupled with ballistic modelling of their trajectory, are crucial to forecast their possible impact in future eruptions. The reliability of such models strongly depends on i) the appropriate physical functions and input parameters and ii) observational validations. In this study, we aimed to unravel intra-conduit processes that strongly control the dynamic of volcanic projectiles by combining numerical modelling and novel experimentally-determined source parameter. In particular, the multiphase ASHEE model (Cerminara 2016; Cerminara et al. 2016) suited for testing post-fragmentation conduit dynamics based on a robust shock tube experimental dataset. By exploding mixtures of pumice and dense lithic particles within a specially designed transparent autoclave, and by using a raft of pressure sensors, ultra-high-speed cameras and pre-sieved natural particles, we observed and quantified: i) kinematic data of the particles and of the gas front along the shock tube and outside, ii) pressure decay at 1GHz resolution. By feeding the ASHEE model with these datasets, and using initial and boundary conditions similar to that of the experiment, we defined domains composed by a pressurized shock tube and the outside chamber at ambient conditions, and tested particles particle motion according to a Lagrangian approach, as well as gas flow with a Eulerian approach (a 3D finite-volume numerical solver, compressible). The comparison between data and model yields estimate of the particle kinematic inside the tube, the pressure evolution at the top and the bottom of the tube, and the eruption source parameters at the tube exit.
description: We designed a series of rapid decompression experiments in which we systematically varied componentry, particle size, and packing arrangement of the initial samples. We also carried empty run experiments, where only the gas phase is decompressed. We used the pressure evolution and high-speed footage of these experiments to i) benchmark the expansion of the gas phase against the expansion of gas and particle mixture, and ii) develop 1D and 3D models of particle acceleration.
DOI: 10.5880/gfz.1.3.2022.001
title: A synthetic dataset of paleo relative sea level observations for testing novel data assimilation approaches

description: This is a synthetic dataset. It was created from the outputs of the glacial isostatic adjustment model VILMA (Klemann et al. 2008). It consists of realtive sea level (RSL) data on a global regular grid. The resolution is 256 x 512 points (Lat x Lon). The tomporal range is from 123 ka BP until present day. Time steps vary between 2.5 kyrs at the beginning and 0.5 kyrs towards the end. The data were created for a specific configuration of the GIA model: lithosphere thickness = 60 km, lithosphere viscosity = 1.0E31 Pa s, upper mantle thickness = 610 km, upper mantle viscosity = 1.0E20 Pa s, lower mantle thickness = 3,221 km, lower mantle viscosity = 1.0E21 Pa s. The RSL data are accompanied by a observation locations mask. This mask was used to identify those locations in the global RSL dataset where real observations are available.
description: The dataset consists of realtive sea level (RSL) data on a global regular grid. The resolution is 256 x 512 points (Lat x Lon). The temporal range is from 123 ka BP until present day. Time steps vary between 2.5 kyrs at the beginning and 0.5 kyrs towards the end. The data were created for a specific configuration of the GIA model: lithosphere thickness = 60 km, lithosphere viscosity = 1.0E31 Pa s, upper mantle thickness = 610 km, upper mantle viscosity = 1.0E20 Pa s, lower mantle thickness = 3,221 km, lower mantle viscosity = 1.0E21 Pa s. The RSL data are accompanied by observation locations masks. These masks were used to mark those locations in the global RSL dataset where real-life observations are available in order to restrict usage of the synthetic data to those locations.
DOI: 10.5880/gfz.1.3.2021.001
title: Mass variations induced by ocean tide oscillations (TiME21)

description: This data publication presents global mass variations that are induced by individual ocean partial tides. The data set was produced using the purely-hydrodynamical ocean tide model TiME in the framework of the DFG-project Nerograv\\ (https://www.lrg.tum.de/iapg/nerograv/) and can be used for gravimetric applications. The overall goal of this project is to improve the processing of gravimetric data sets (e.g. GRACE/GRACE-FO) by improving the understanding of sensor data, processing strategies, and background models. The here presented DOI can contribute to this goal as the here described tidally induced mass variations are an important part of the described background models. As ocean tides are usually described as a superposition of so-called partial tides, the presented mass variations can be attributed to single partial tide frequencies and are thus represented for single partial tide frequencies. Here, not only the effect of direct gravitation exerted by the ocean water is included but also gravity variations due to the elastic yielding of the solid earth in response to water mass redistribution (the load tide) are allowed for. The information describing the partial tides has been transformed to fully normalized Stokes Coefficients describing in-phase and quadrature fields as those are especially handy for gravimetric purposes. The next section describes the creation of the data in more detail.
DOI: 10.5880/gfz.4.8.2022.002
title: Geochemistry of late-Variscan felsic igneous rocks of the Erzgebirge-Vogtland metallogenic province - Part 2: F-poor biotite and two-mica granites

description: This data set is Part 2 of the compiles whole-rock chemical data for late-Variscan low-F biotite and two-mica granites in the German Erzgebirge, in the Saxothuringian Zone of the Variscan Orogen. The group of F-poor biotite granites is represented by the composite massifs of Kirchberg and Niederbobritzsch, the Plohn Granite Suite (PGS), the Aue Granite Suite (AGS), and the subsurface granites of Beiersdorf und Bernsbach. For the group of two-mica granites, compositional data for the multi-stage Bergen massif and the granites from Lauter and Schwarzenberg are reported (Figure 1). Crystal-melt fractionation was the dominant process controlling the evolution of bulk composition in the course of massif/pluton formation. However, metasomatic and hydrothermal processes involving late-stage residual melts and high-T late- to post-magmatic fluids became increasingly more important in highly evolved units and have variably modified the abundances of mobile elements. Interaction with the various metamorphic country rocks and infiltration of meteoric low-T fluids have further disturbed the initial chemical patterns in the endocontact zones and zones influenced by surface weathering. The data set reports whole-rock geochemical analyses for enclaves, granites, aplites, endocontact rocks, and some facial varieties. The data are presented as Excel (xlsx) and machine-readable txt formats. The content of the excel sheet and further information on the granites and regional geology are provided in the data description file.
DOI: 10.5880/gipp-mt.201810.1
title: Site characterization of the PIER-ICDP drill holes by imaging the subsurface electrical conductivity structure: local and regional structure beneath Mýtina and Neualbenreuth Maar (ConeEM)

description: The West Bohemian Massif as part of the geodynamically active European Cenozoic Rift System is characterised by ongoing magmatic processes in the intra-continental lithospheric mantle. A series of phenomena such as massive degassing of CO2 and repeated earthquake swarms make the Eger Rift a unique target area for European intra-continental geo-scientific research. The ICDP project "Drilling the Eger Rift" was funded to study the field of earthquake-fluid-rock-biosphere interaction. In the framework of this ICDP project, magnetotelluric (MT) experiments have been conducted to image the subsurface distribution of the electrical conductivity down to depths of several tens of kilometres as the electrical conductivity is particularly sensitive to the presence of high-conductive phases such as aqueous fluids, partial melts or metallic compounds. Based on recent MT experiments in 2015/2016, Munoz et al. (2018) presented 2D images of the electrical conductivity structure along a NS profile across the Eger Rift. It reveals a conductive channel at the earthquake swarm region that extend from the lower crust to the surface forming a pathway for fluids up to the region of the mofettes. A second conductive channel is present in the south of the model. Due to the given station setup along a profile, the resulting 2D inversion allows ambiguous interpretations of this feature. As 3D inversion is required to distinguish between the different interpretations, we conducted another MT field experiment at the end of 2018. This data publication (10.5880/GIPP-MT. 201810 .1) encompasses a detailed report in pdf format with a description of the project, information on the experimental setup, data collection, instrumentation used, recording configuration and data quality. The folder structure and content of the data repository are described in detail in Ritter et al. (2019). Time-series data are provided in EMERALD format (Ritter et al., 2015).
description: The Geophysical Instrument Pool Potsdam (GIPP) provides field instruments for (temporary) seismological studies (both controlled source and earthquake seismology) and for magnetotelluric (electromagnetic) experiments. The GIPP is operated by the GFZ German Research Centre for Geosciences. The instrument facility is open for academic use. Instrument applications are evaluated and ranked by an external steering board. See Haberland and Ritter (2016) and https://www.gfz-potsdam.de/gipp for more information.
DOI: 10.5880/gipp-mt.200607.1
title: Integrated Geophysical Exploration Technologies for Deep Fractured Geothermal Systems. Report on the magnetotelluric data of project IGET.2006

description: The Integrated Geophysical Exploration Technologies for Deep Fractured Geothermal Systems project (I-GET) was aimed at developing an innovative strategy for geophysical exploration, particularly to exploit the full potential of seismic and electromagnetic exploration methods in detecting permeable zones and fluid bearing fractures. The proposed geothermal exploration approach was applied in selected European geothermal systems with different geological and thermodynamic reservoir characteristics: in Italy (high enthalpy reservoir in metamorphic rocks), in Iceland (high enthalpy reservoir in volcanic rocks) and in Germany and Poland (low to middle enthalpy reservoir in sedimentary rocks). The Groß Schönebeck in-situ geothermal laboratory, located 40 km north of Berlin in northeastern Germany, is a key site for testing the geothermal potential of deep sedimentary basins. The target reservoir is located in Lower Permian sandstones and volcanic strata, which host deep aquifers throughout the Northeast German Basin (NEGB). The laboratory consists of two 4.3-km-deep boreholes. The electrical conductivity of the subsurface is a very important parameter for characterizing geothermal systems as hot and mineralized (saline) fluids of deep aquifers can be imaged as regions of high electrical conductivity. In the first phase of the I-GET project, carried out in summer 2006, MT data was recorded at 55 stations along a 40-km long profile. In order to reduce the effect of the cultural noise, 4 remote reference stations located at distances of about 100 km from the profile were used. This profile is spatially coincident with a seismic tomography profile (Bauer et al., 2010). The main objective of the geophysical site characterization experiments was to derive combined electrical conductivity and P- and S-velocity tomographic models for a joint interpretation in high resolution. The data are provided in EMERALD format (Ritter et al., 2015). The folder structure and content is described in detail in Ritter et al., 2019. The project specific description is available in the associated data description file including information on the experimental setup and data collection, the instrumentation, recording configuration and data processing. Scientific outcomes of this project were published by Muñoz et al., (2010a, 2010b).
DOI: 10.5880/gipp-mt.201922.1
title: MT_ANT2 - Magnetotelluric Measurements Around Neumayer Station III, Antarctica

description: Magnetotellurics (MT) is a geophysical deep sounding tool that can help decipher the deep hydrology and geology of Antarctica, in concert with more established and already applied geophysical methods, such as seismology, gravity, and magnetics. Electrical conductivity is an important physical parameter to identify properties of rocks and, perhaps more importantly, constituents within, such as fluids or mineralisation.The unique conditions of Antarctica, which is largely covered with ice cause technical issues, particularly with the electric field recordings, as highly resistive snow and ice at surface of Antarctica hampers contact of the E-field sensors (telluric electrodes) with the ground. The project was a feasibility study to address this principal problem and to test modified MT equipment of the Geophysical Instrument Pool Potsdam (GIPP) in the vicinity of the Neumayer Station III (NMIII) on the Ekström Ice Shelfon. This data publication encompasses a detailed report in .pdf format with a description of the project, information on the experimental setup, data collection, instrumentation used, recording configuration and data quality. The folder structure and content of the data repository are described in detail in Ritter et al. (2019). Time-series data are provided in EMERALD format (Ritter et al., 2015).
description: The Geophysical Instrument Pool Potsdam (GIPP) provides field instruments for (temporary) seismological studies (both controlled source and earthquake seismology) and for magnetotelluric (electromagnetic) experiments. The GIPP is operated by the GFZ German Research Centre for Geosciences. The instrument facility is open for academic use. Instrument applications are evaluated and ranked by an external steering board. See Haberland and Ritter (2016) and https://www.gfz-potsdam.de/gipp for more information.
DOI: 10.5880/gipp-mt.201423.1
title: Mapping of the Whitehill Formation in the Eastern Karoo Basin near Jansenville

description: The South African Karoo Basin, which is known for its potentially shale gas bearing formations, was the target of an extensive research programme launched by the Nelson Mandela University, South Africa. The aim of this project was to obtain a fundamental understanding of the geology, petrology and hydrology of the sedimentary layers. In 2014, Magnetotelluric (MT) measurements were conducted in the Eastern Karoo Basin to image the electrical conductivity structure of the shallow subsurface and to develop a three-dimensional (3D) model. Previous studies by Weckmann et al. (2007a, b) and Branch et al. (2007) identified the potentially shale gas bearing Whitehill Formation as an electrically conductive sub-horizontal layer, which covers large parts of the Karoo Basin. The increased interest in future shale gas exploration raised concerns regarding the potential impact on aquifers in this water scarce and fragile environment. Since the electrical conductivity is sensitive to fluids, imaging both, the black shale horizon and the deep aquifer system in this region was the ultimate goal of the MT study. Our field experiment is designed to serve as a baseline study before any activity regarding shale gas exploitation commenced. With high resolution 2D and regional 3D inversion and forward models several aquifers, the Whitehill formation and the possible source region of the Beattie Magnetic Anomaly could be mapped.This data publication (10.5880/GIPP-MT.201423.1) encompasses a detailed report in pdf format with a description of the project, information on the experimental setup, data collection, instrumentation used, recording configuration and data quality. The folder structure and content of the data repository are described in detail in Ritter et al. (2019). Time-series data are provided in EMERALD format (Ritter et al., 2015).
description: The Geophysical Instrument Pool Potsdam (GIPP) provides field instruments for (temporary) seismological studies (both controlled source and earthquake seismology) and for magnetotelluric (electromagnetic) experiments. The GIPP is operated by the GFZ German Research Centre for Geosciences. The instrument facility is open for academic use. Instrument applications are evaluated and ranked by an external steering board. See Haberland and Ritter (2016) and https://www.gfz-potsdam.de/gipp for more information.
DOI: 10.5880/gipp-mt.201933.1
title: Magnetotelluric and Radiomagnetotelluric measurements near Geyer in the Ore Mountains, Germany

description: The region of Geyer in the Ore Mountains (Erzgebirge) of Germany, situated approximately 110 kilometres south of Leipzig, has a long history of ore mining. The region is known for its deposits of tin, zinc, tungsten, molybdenum, copper, iron, silver, and indium. Due to this long history and known reservoir potential, this area was selected as a test site for the Innovative, Non-invasive and Fully Acceptable Exploration Technologies (INFACT) project. INFACT is a EU funded project aiming to foster new and innovative non-invasive methods for the exploration of new mineral deposits and is coordinated by the Helmholtz Institute Freiberg for Resource Technology (HIF) at Helmholtz-Zentrum Dresden-Rossendorf (HZDR). Within the framework of this project, the GFZ - German Research Centre for Geosciences, Potsdam, Germany, acquired magnetotelluric (MT) and radiomagnetotelluric (RMT) data near Geyer. The main objectives of these measurements were to map the shallow subsurface for mineral deposits and to evaluate the potential of these methods in densely populated areas with high levels of anthropogenic noise. This data publication (10.5880/GIPP-MT.201933.1) encompasses a detailed report in pdf format with a description of the project, information on the experimental setup, data collection, instrumentation used, recording configuration and data quality. The folder structure and content of the data repository are described in detail in Ritter et al. (2019). Time-series data are provided in EMERALD format (Ritter et al., 2015).
description: The Geophysical Instrument Pool Potsdam (GIPP) provides field instruments for (temporary) seismological studies (both controlled source and earthquake seismology) and for magnetotelluric (electromagnetic) experiments. The GIPP is operated by the GFZ German Research Centre for Geosciences. The instrument facility is open for academic use. Instrument applications are evaluated and ranked by an external steering board. See Haberland and Ritter (2016) and https://www.gfz-potsdam.de/gipp for more information.
DOI: 10.15468/dl.yetmvc
title: Occurrence Download

description: A dataset containing 20 species occurrences available in GBIF matching the query:
{
 "and" : [
 "TaxonKey is Zygotritonia praecox",
 "Continent is Africa"
 ]
}

 The dataset includes 20 records from 6 constituent datasets; see https://api.gbif.org/v1/occurrence/download/0044074-251120083545085/datasets/export for details.
 
Data from some individual datasets included in this download may be licensed under less restrictive terms.
DOI: 10.5880/gipp-mt.201527.1
title: Magnetotelluric measurements in the Mérida Andes, western Venezuela

description: The 100 km wide Mérida Andes extend from the Colombian/Venezuelan border to the Caribbean coast. To the north and south, the Mérida Andes are bound by hydrocarbon-rich sedimentary basins. This mountain chain and its associated major strike-slip fault systems formed by the oblique convergence of the Caribbean with the South American Plate and the north-eastwards expulsion of the North Andean Block in western Venezuela. In 2013, the Integrated Geoscience of the Mérida Andes Project (the GIAME project) was initiated to image the Mérida Andes on a lithospheric scale and to develop a dynamic model of their evolution by integrating wide-angle seismic, magnetotelluric and potential field data. Magnetotelluric (MT) dataset was acquired in 2015 along a 240 km long profile across the Mérida Andes. MT studies of orogens often reveal complex resistivity structures, typically associated with active deformation and characterized by high electrical conductivity zones. Fluids in fault systems and fluids derived from remineralization reactions of hydrous minerals often characterise high conductivity in active tectonic regimes. Cruces-Zabala et al. (2020) identified conductive zones with up to 10 km depth for the Maracaibo Basin and 5 km for the Barinas - Apure Basin. The Mérida Andes are charaterized by high resistivity separated by several conductive anomalies that corelate spatialy to the fault systems at the surface. A conductive zone a great depth (&gt;50km) was identified as a projection of the detachment surface of the Trujillo Block to the east. This data publication encompasses a detailed report in pdf format with a description of the project, information on the experimental setup, data collection, instrumentation used, recording configuration and data quality. The folder structure and content of the data repository are described in detail in Ritter et al. (2019). Time-series data are provided in EMERALD format (Ritter et al., 2015).
description: The Geophysical Instrument Pool Potsdam (GIPP) provides field instruments for (temporary) seismological studies (both controlled source and earthquake seismology) and for magnetotelluric (electromagnetic) experiments. The GIPP is operated by the GFZ German Research Centre for Geosciences. The instrument facility is open for academic use. Instrument applications are evaluated and ranked by an external steering board. See Haberland and Ritter (2016) and https://www.gfz-potsdam.de/gipp for more information.