375 documents found in 472ms
# 11
Dahle, Christoph • Flechtner, Frank • Murböck, Michael • Michalak, Grzegorz • Neumayer, Hans • (et. al.)
Abstract: Spherical harmonic coefficients representing an estimate of Earth's mean gravity field during the specified timespan derived from GRACE mission measurements. These coefficients represent the full magnitude of land hydrology, ice, and solid Earth processes. Further, they represent atmospheric and oceanic processes not captured in the accompanying GAC product.
# 12
Rosenau, Matthias • Pohlenz, Andre • Kemnitz, Helga • Warsitzka, Michael
Abstract: This dataset provides friction data from ring-shear tests (RST) for a quartz sand (type “G23”). This material is used in various types of analogue experiments in the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam for simulating brittle rocks in the upper crust (e,g. Kenkmann et al., 2007; Contardo et al., 2011; Reiter et al., 2011;Warsitzka et al., 2013; Santimano,et al., 2015; Warsitzka et al., 2015; Ritter et al., 2016; 2018 a,b). The material has been characterized by means of internal friction coefficients µ and cohesions C. According to our analysis the material shows a Mohr-Coulomb behaviour characterized by a linear failure envelope and peak, dynamic and reactivation friction coefficients of µP = 0.73, µD = 0.57 and µR = 0.65, respectively. Cohesions C are in the order of 10 – 120 Pa. The material shows a minor rate-weakening of <1% per ten-fold change in shear velocity v. Further information about materical characteristics, measurement procedures, sample preparation, the RST (Ring-shear test) and VST (Velocity stepping test) procedure, as well as the analysed method is proviced in the data description file. The list of files explains the file and folder structure of the data set.
# 13
Rosenau, Matthias • Pohlenz, Andre • Kemnitz, Helga • Warsitzka, Michael
Abstract: This dataset provides friction data from ring-shear tests (RST) for a quartz sand (“G12”). This material is used in various types of analogue experiments in the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam for simulating brittle rocks in the upper crust. The material has been characterized by means of internal friction coefficients µ and cohesions C. According to our analysis the material shows a Mohr-Coulomb behaviour characterized by a linear failure envelope and peak, dynamic and reactivation friction coefficients of µP = 0.69, µD = 0.55 and µR = 0.62, respectively. Cohesions C are in the order of 50 – 110 Pa. The material shows a minor rate-weakening of <1% per ten-fold change in shear velocity. Further information about materical characteristics, measurement procedures, sample preparation, the RST (Ring-shear test) and VST (Velocity stepping test) procedure, as well as the analysed method is proviced in the data description file. The list of files explains the file and folder structure of the data set.
# 14
Korte, Monika • Brown, Maxwell • Gunnarson, Sydney
Abstract: Global spherical harmonic paleomagnetic field model LSMOD.1 describes the magnetic field evolution from 50 to 30 ka BP based on published paleomagnetic sediment records and volcanic data. The time interval includes the Laschamp (~41 ka BP) and Mono Lake (~34 ka BP) excursions. The model is given with Fortran source code to obtain spherical harmonic magnetic field coefficients for individual epochs and to obtain time series of magnetic declination, inclination and field intensity from 49.95 to 30 ka BP for any location on Earth. For details see M. Brown, M. Korte, R. Holme, I. Wardinski and S. Gunnarson (2018): Earth's magnetic field is probably not reversing. PNAS, 115, 5111-5116.
File overviewLSMOD.1 -- ASCII file containing the time-dependent model by a list of spline basis knot points and spherical harmonic coefficients for these knot points.LSfield.f -- Fortran source code to obtain time series predictions of declination, inclination and intensity from the model file.LScoefs.f -- Fortran source code to obtain the spherical harmonic coefficients for an individual age from the time-dependent model file. The data are licenced under the Creative Commons Attribution 4.0 International Licence (CC BY 4.0) and the Fortran Codes under the Apache License, Version 2.0. The Fortran source code should work with any standard Fortran 77 or higher compiler. Each of the two program files can be compiled separately, all required subroutines are included in the files. The model file, LSMOD.1 or LSMOD.2, is read in by the executable program and has to be in the same directory. The programs work with interactive input, which will be requested when running the program.
# 15
Codeço, Marta S. • Weis, Philipp • Trumbull, Robert B. • van Hinsberg, Vincent • Pinto, Filipe • (et. al.)
Abstract: Geochemistry is one of the most important tools for exploring and understanding mineral resources. Typically, hydrothermal ore deposits are characterized by primary alteration halos. At Panasqueira, the hydrothermal alteration forms a variably thick alteration halo, characterized by a strong tourmalinization (± muscovitization) of the wall rocks enclosing the mineralized veins. Tourmaline and mica are ubiquitous minerals at the world-class Panasqueira W-Sn-Cu deposit and coexist in many others hydrothermal ore deposits worldwide. Both minerals are well-known to host variable amounts of trace elements and therefore suitable was tracers for fluid source and composition. Major, minor and trace elements of the altered and unaltered metasediments from Panasqueira area were analysed by XRF and ICP-MS. We further analyzed tourmaline and white mica major, minor and trace elements compositions by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in previously well-characterized samples from different locations/setting in the mine (greisen, vein-selvages, wall-rock alteration zones, fault zone and late-vugs). Detailed information about the the samples used, the location and general geological background of the samples and the analytical methods are provided in the data description file (2019-001_Codeco-et-al_data-description.pdf).
Panasqueira is a world-class W-Sn-Cu lode-type deposit located in Castelo Branco district (Beira Baixa, central Portugal). The ore deposit consists of a swarm of sub-horizontal veins associated to a Late-Variscan S-type granite and enclosed by a metasedimentary unit of Late Ediacaran to Early Cambrian age (e.g., Kelly and Rye, 1979; Romão et al., 2013).The veins are mainly composed of gangue quartz, muscovite and minor carbonates, apatite, topaz, topaz, fluorite, tourmaline, rutile, ilmenite, arsenopyrite, sphalerite, pyrite, marcasite, stannite and pyrrhotite. Mineralization of wolframite, chalcopyrite and cassiterite is predominantly hosted in veins with minor stringers and lenses of sulfide minerals in the wall rocks (e.g., Kelly and Rye, 1979; Polya, 1989; Polya et al., 2000). Although there is a strong variation in the vein mineralogy, typically the quartz vein-filling is rimmed by a muscovite up to 4-5 cm thick. The hydrothermal alteration produced a 2 to 30 cm thick tourmaline-rich alteration halo in the host metasediments (Bussink, 1984).
The analyzed samples are described by Codeço et al. (2017), Codeço et al. (2018) and Codeço et al. (in prep.). In those works, chemical (major and trace elements) and boron isotopic compositions of tourmaline and white mica, and whole rock chemistry of altered and unaltered metasediments are presented and discussed. Further details on sample description can be found in the file “SampleDescription.xlsx”. Figure 2 shows the location of the drill holes were samples for petrography and whole rock geochemistry were collected and of the samples containing tourmaline and mica.
# 16
Reiter, Karsten • Kukowski, Nina • Ratschbacher, Lothar • Rosenau, Matthias
Abstract: This data publication includes animations and figures of eight scaled analogue models that are used to investigate the evolution of a curved mountain belt akin to the Pamir and Hindu Kush orogenic system and adjacent Tadjik basin. Crustal deformation is simulated by means of indentation of two basement blocks into a sedimentary sequence and the formation of a curved fold-and-thrust belt.The experimental set-up has two adjacent rigid indenters representing the basement blocks moving in parallel with a velocity difference (Figure 1). The slow indenter moves with a relative velocity ranging from 40 to 80% of that of the fast one. A layer of quartz sand in front of the indenters, 1 by 1 meter in size and 1.5 cm thick, represents the sedimentary basin infill. A basal detachment layer is made up of low-friction glass beads or viscous silicone oil representing weak shale or evaporates layers, respectively. The surface evolution by means of topography and strain distribution is derived from 3-D particle image velocimetry (PIV). This allows visualizing and analysing the development of the model surface during the complete model run at high spatio-temporal resolution. All details about the model set-up, modelling results and interpretation can be found in Reiter et al. (2011).The here provided additional material includes time-lapse movies showing the topographic evolution of the eight models. These visualizations are oblique views played back at 60-fold velocity for the “glass beads experiments” (gb40 to gb80) and 3600-fold velocity for the “silicone experiments” (si60, si-gb60).In addition to the experiment movies we provide a set of figures. The figures include surface views as well as cross-sections through the finite models highlighting the link between topography and internal structure of the simulated curved fold-and-thrust belts. Additionally, attribute maps of distinct morphometric measures (curvature, slope) and deformation parameters (uplift, horizontal translation) for the experiments with glass beads detachments are given. Finally, the movie “Experimenting.avi” shows in time-lapse the whole workflow of setting up, conducting and documenting an experiment, which originally required three days (for experiment si-gb60).An overview on the parameters used in the experimental series of the movie sequences is given in the explanatory file (Explanations_Reiter-et-al-2016.pdf). A full list of files is given in “list-of-files-Reiter-et-al-2016.pdf”.
# 17
Rudolf, Michael • Boutelier, David • Rosenau, Matthias • Schreurs, Guido • Oncken, Onno
Abstract: The datasets that are presented here have been obtained to provide a rheological benchmark of silicones used in various analog modeling laboratories. The data contains rheological measurements of several polydimethylsiloxanes (PDMS) and filled silicone oils. The samples of eight different silicone oils originate from seven laboratories. Each sample was analyzed using rotational controlled shear rate tests (CSR), temperature sweep test, and dynamical oscillation tests (amplitude and frequency sweeps). Detailed information on the analysis and interpretation of the data is found in Rudolf, et al. (2016).The data is provided as comma-separated files in *.csv format. Each file contains multiple measurements, each starting with own data series information that is followed by the actual measurement in the form of a table including the individual units of measure. Furthermore the results from ReSpect (Takeh & Shanbhag, 2013) for the discrete Maxwell relaxation spectra are provided. All files can be opened using a text-editor, MS Excel, or equivalent software.More information about the datasets is available in the file Explanations_Rudolf-et-al-2016.pdf, an overview on the available files in the List_of_Files_Rudolf-et-al-2016 (in .pdf and .xlsx format). All information and overview files are also included in Rudolf-et-al-2016_datasets.zip.
# 18
Willingshofer, Ernst • Sokoutis, Dimitrios • Beekman, Fred • Schönebeck, Jan-Michael • Warsitzka, Michael • (et. al.)
Abstract: This dataset provides friction data from ring-shear tests (RST) on feldspar sand and quartz sand, which are used to simulate brittle behaviour in crust- and lithosphere-scale analogue experiments at the Tectonic Laboratory (TecLab), Utrecht University (NL) (Willingshofer et al., 2005; Willingshofer & Sokoutis, 2009; Athmer et al., 2010; Luth et al., 2010; Fernández-Lozano et al., 2011; Leever et al., 2011; Sokoutis & Willingshofer, 2011; Fernández-Lozano et al., 2012; Luth et al., 2013; Munteanu et al., 2013; Willingshofer et al., 2013; Munteanu et al., 2014; Calignano et al., 2015a, b; Ortner et al., 2015; Gabrielsen et al., 2016; Calignano et al., 2017; van Gelder et al., 2017; Wang et al., 2017; Beniest et al., 2018 ). The materials have been characterized by means of internal friction coefficients µ and cohesions C as a remote service by the Helmholtz Laboratory for Tectonic Modelling (HelTec) at the GFZ German Research Centre for Geosciences in Potsdam. According to our analysis both materials show a Mohr-Coulomb behaviour characterized by a linear failure envelope. Peak, dynamic and reactivation friction coefficients of the feldspar sand are µP = 0.68, µD = 0.55, and µR = 0.61, respectively. Friction coefficients of the quartz sand are µP = 0.63, µD = 0.48, and µR = 0.52, respectively. Cohesions of the feldspar sand and the quartz sand are in the order of few tens of Pa. A minor rate-weakening of 1% per ten-fold rate change is evident for the feldspar sand, whereas the quartz sand shows a significant rate weakening of ~5%. Further information about materical characteristics, measurement procedures, sample preparation, the RST (Ring-shear test) and VST (Velocity stepping test) procedure, as well as the analysed method is proviced in the data description file. The list of files explains the file and folder structure of the data set.
# 19
Broerse, Taco • Norder, Ben • Picken, Stephen • Govers, Rob • Willingshofer, Ernst • (et. al.)
Abstract: This dataset provides strain and strain rate data on mixtures of plasticine, silicone oils and iron powder that has been used in slab break-of analogue experiments in the Tectonic Laboratory (TecLab) at Utrecht University (NL) as an analogue for viscously deforming lithosphere. The materials have been analyzed in a creep and recovery test, applying a parallel plate setup using an AR-G2 rheometer (by TA Instruments). The materials can in general be described as viscoelastic materials with a power-law rheology (see previous work on plasticine-silicone polymer mixtures Weijermars [1986], Sokoutis [1987], Boutelier et al. [2008]). For a couple of the tested materials we find a complementary Newtonian behavior at the low end of the tested stress levels, with a transition to power-law behavior at increasing stress. Furthermore, the materials exhibit elastic and anelastic (recoverable) deformation. The corresponding paper (Broerse et al., 2018) describes the rheology, while this supplement describes the raw data and important details of the measurement setup. The raw data concerns mostly (uncorrected) strain and strain rate data. The rheometry has been performed at the Advanced Soft Matter group at the Department of Chemical Engineering, Delft University of Technology, The Netherlands.
# 20
McBeck, Jessica • Cooke, Michele • Souloumiac, Pauline • Maillot, Bertrand • Mary, Baptiste
Abstract: Tracking the evolution of the deformational energy budget within accretionary systems provides insight into the driving mechanisms that control fault development. To quantify the impact of these mechanisms on overall system efficiency, we estimate energy budget components as the first thrust fault pair develops in dry-sand accretion analogue experiments. This data set includes photos taken and forces measured in four experiments performed at Université de Cergy-Pontoise in October-November 2016. The experiments are described in McBeck et al. (submitted). The data are organized into 5 main folders, with the following contents:1) E373_photos: Contains 3 subfolders: droit_RDY, gauche_RDY, haut_RDY. Each subfolder contains images taken at 1 second intervals throughout experiment. droit_RDY, gauche_RDY, and haut_RDY contain photos of the right, left, and top of the sandpack.2) E374_photos: Same organization and contents of folder E373_photos3) E375_photos: Same organization and contents of folder E373_photos4) E376_photos: Same organization and contents of folder E373_photos5) forces: Contains text files that list the normal force against the backwall (N) and total applied normal displacement to the backwall (mm) in the second and first columns, respectively. The filename indicates which experiment the text file describes.
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