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Titanium stable isotope and major and trace element compositions of Archean and Paleoproterozoic sanukitoids and Paleozoic high Ba-Sr granite suites

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Major element stream water chemistry, compiled 10Be erosion rates, and analyses of weathering across an erosion-rate gradient in in southern Taiwan

This dataset was used to analyse the link between chemical weathering and erosion rates across the southern tip of Taiwan. The weathering of silicate minerals is a key component of Earth’s long-term carbon cycle, and it stabilises Earth’s climate by sequestering carbon dioxide (CO2) from the atmosphere – thereby balancing CO2-emissions from the mantle. Conversely, the weathering of accessory carbonate and sulphides acts as a CO2 source. Chemical weathering is fundamentally dependent on the exposure of fresh minerals by erosion. With these data we investigated the link between the exposure of rocks by erosion and the chemical weathering of silicates, carbonates, and sulphides across a landscape with a significant erosion-rate gradient and comparatively little variation in runoff and lithology. This dataset includes new major element chemistry and water isotopes of river waters collected from across the southern tip of Taiwan as well as associated topographic and lithologic data (tab 1 in the excel table). Moreover, the data include a compilation of published 10Be-derived erosion rates from a subset of the sampled rivers (tab 2 in the excel file) and available major element chemistry from hotsprings in the region (tab 3 in the excel file). Using a mixing model, we derived the cation contributions from silicate and carbonate weathering as well as from hotspring and cyclic sources. Further, we estimated the erosion rates for each sample from the compiled 10Be data and the steepness of river channels, and we estimated saturation and pH in the weathering zone. For more information please refer to the associated data description file and especially to Bufe et al. (2021).

Radiogenic isotope compositions of eruption products from the 2019 paroxysmal eruptions at Stromboli Volcano

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Sample information, major element stream chemistry, inversion model setup and results, sample corrections for precipitation and degassing, and CO2 exchange calculations

Tables that include information and calculations associated with water samples collected from rivers in Central Italy. The goal of the project was to determine the carbon budget for the Central Apennine Mountains of Italy, by accounting for weathering reactions that are responsible for either CO2 drawdown or release into the atmosphere. The carbon budget was created by: 1) analysing samples from different water bodies and sources in the Central Apennines (rivers, lakes, and groundwater) for ion and isotope signatures, and 2) by incorporating the ion and isotope signatures from the waters into an inversion model that partitions these signatures into different sources (e.g. minerals, vegetation, atmospheric sources) around the landscape. All data associated with this publication are provided in a single excel spreadsheet that contains a separate tab for each of the 18 Tables. The supplementary data include: 1) Information on the locations of the water samples and associated water bodies, described in the “Sampling Methods” section, 2) ion and isotope measurements from the water samples, described in the “Analytical Procedure” section, 3) the setup and output from the inversion model, and 4) the CO2 calculations that form the basis for the carbon budget, described in the “Data Processing” section. Water samples were collected over two seasons, in winter and summer; data in the tables are divided by sampling season, where indicated in the content description. For a full description of the sampling strategy, data, and methods, please refer to: Erlanger et al. (2024) “Deep CO2 release and the carbon budget of the central Apennines modulated by geodynamics” Nature Geoscience.

Copper isotope fractionation during prehistoric smelting of copper sulfides: experimental and analytical data

The project from which the data derived aimed to establish the first systematic study of Cu isotope fractionation during the prehistoric smelting and refining process. For this reason, an experimental approach was used to smelt sulfide copper ore according to reconstructed prehistoric smelting models. The ore was collected by E. Hanning as part of her PhD thesis work from a Bronze Age mining site, the Mitterberg region, Austria (Hanning and Pils 2011) and was made available for the experiments.All starting materials for the experiments such as the natural ore, roasted ore, construction clay, flux, dung (used for the roasting), wood and charcoal (fuel) were natural materials. All firing conditions including the amount of fuel or charging material and the temperatures in the furnaces were recorded, and the experimental procedures were documented in the very detail. In total, 30 experiments were carried out in 4 experimental series. The smelting products, both intermediate products and final products were sampled during or after the respective experiment. Slag, matte and copper metal were the major smelting products. All other materials used in and produced by the experiments were sampled, too. Materials used and produced in the two most promising experimental series with regard to potential Cu isotope fractionation were analyzed. Based on the analytical results, the potential of Cu isotopes as a tool in archaeometallurgical research was systematically evaluated and consequences for the copper isotope application as a provenance tool in archaeometry were identified.The data include the documentation of the experiments, laboratory procedures and analytical methods. An experimental outline was previously published in Rose et al. (2019). Analytical methods applied were ICP-MS (elemental analysis, 80 samples), MC-ICP-MS (copper isotopes, 98 samples), and XRD (phase analysis, 25 samples). The experiments were carried out at the Römisch-Germanisches Zentralmuseum, Labor für Experimentelle Archäologie, Mayen, Germany. Laboratories used for the analytical part of the project were the research laboratories at the Deutsches Bergbau-Museum Bochum and FIERCE (Frankfurt Isotope and Element Research Center), Goethe-University Frankfurt, both Germany. Data were processed and plots created with R (R Core Team 2019) in RStudio®. Data are provided as data tables or text files, the R scripts used to create the time-temperature plots of the smelting experiments are also included.The full description of the data and methods is provided in the data description file.

Whole-rock geochemistry of rock units from the Pfitscher Joch area, Western Tauern Window

In the Western Tauern Window, Zillertal Alps (Austria/Italy), metasediments of a Mesozoic intra-montane basin ("Pfitsch-Mörchner basin"; Veselá and Lammerer, 2008) are exposed. The (me-ta)sediments were deposited on a Variscan basement, which comprises different types of meta-granitoids and their (Pre)-Variscan metamorphic country rocks. The chemical composition (major and trace elements) of these rocks is presented for 205 samples. In the metasediments (103 samples), we distinguish the following units (from base to top): metaconglomerate (14 samples) – mica schist (19) – carbonate-mica schist (9) – tourmaline gneiss (35) – lazulite quartzite (25) – marble (1). In the basement to the NW of the basin, we distinguish two different types of orthogneiss (both Zentralgneis of the Tux unit, in the local nomenclature two varieties Augenflasergneis and Schrammacher gneiss; 32 samples) and the roof pendant of these gneisses with serpentinite (10 samples), amphibolite, and paragneiss (no analyses presented). In the SE of the basin we distinguish orthogneiss from the Zillertal branch of the Zentralgneis (7 samples), biotite-chlorite-plagioclase gneiss (9 samples), amphibolite, and (Pre-)Variscan graphitic micaschist with the local name Furtschagl schist (no analyses presented), and at the base of the basin sediments a schistose pyrite quartzite (31) with lenses of magnetite-chloritoide-staurolite-chlorite rich rocks (13 samples MCSC-lenses, interpreted as paleosol, Barrientos and Selverstone, 1987). From a subset of these samples (23 samples), rare earth elements were determined, and from another subset of 25 samples 11B/10B boron isotope ratios and whole rock B-contents. This extends a previously published data set of B isotope ratios in tourmaline from the metasedimen-tary unit (Berryman et al. 2017). For a test of stratigraphic correlation, typical rocks from the meta-conglomerate, the carbonate-mica schist, lazulite quartzite, and marble (one sample each) were analyzed for 87Sr/86Sr isotope ratios.

PRESSurE Kahule Khola gauging station data Nepal

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

Isotopic data of pyrite (δ34S) and barite (δ34S, δ18O) in the Canol Formation (Selwyn Basin, Canada)

The stable isotopic composition of pyrite (δ34Spyrite) and barite (δ34Sbarite, δ18Obarite) in marine sedimentary rocks provides a valuable archive for reconstructing the biogeochemical processes that link the sulfur, carbon, and iron cycles. Highly positive δ34Spyrite values that exceed coeval unmodified seawater sulfate (δ34Spyrite > δ34SSO4(SW)), have been recorded in both modern sediments and ancient sedimentary records and are interpreted to result from various biotic and abiotic processes under a range of environmental conditions. A host of processes, including basin restriction, euxinia, low seawater sulfate, dissimilatory microbial sulfate reduction, sulfide reoxidation, and sulfur disproportionation, have been suggested to account for the formation of highly positive δ34Spyrite values in marine environments. Significantly, determining which of these factors was responsible for the pyrite formation is impeded by a lack of constraints for coeval sulfate, with relatively few examples available where δ34Spyrite and proxies for δ34Ssulfate values (e.g., barite) have been paired at high resolution. In the Selwyn Basin, Canada, the Late Devonian sedimentary system is host to large, mudstone-hosted bedded barite units. These barite units have been interpreted in the past as distal expressions of SEDEX mineralization. However, recent studies on similar settings have highlighted how barite may have formed by diagenetic processes before being subsequently replaced during hydrothermal sulfide mineralization. Coincidentally, highly positive δ34Sbarite values have been recorded in such barite occurring coevally with pyrite in diagenetic redox front, where sulfate reduction is coupled to anaerobic oxidation of methane (SR-AOM) at the sulfate methane transition zone (SMTZ). The mechanisms of sulfur cycling and concurrent processes are, nevertheless, poorly constrained. Grema et al. (2021) integrate high-resolution scanning electron microscopy petrography of barite (+ associated barium phases) and pyrite, together with microscale isotopic microanalyses of δ34Spyrite, δ34Sbarite, and δ18Obarite of selected samples from the Late Devonian Canol Formation of the Selwyn Basin. Samples containing both barite and pyrite were targeted to develop paired isotopic constraints on the evolution of sulfur during diagenesis. We have focused on the precise mechanism by which highly positive δ34Spyrite values developed in the Canol Formation and discuss the implications for interpreting sulfur isotopes in similar settings. This data report comprises microscale secondary ion mass spectrometry (SIMS) analyses of the isotopic compositions of pyrite (δ34Spyrite; n= 200) and barite (δ34Sbarite; n= 485, δ18Obarite; n= 338) in nine stratigraphic sections of the Northwest Territories’ part of the Selwyn Basin. Microdrills of regions of interest (n= 54) were made on polished sections to obtain suitable subsamples, using a 4 mm diameter diamond core drill. Several representative subsamples were cast into 25 mm epoxy pucks, together with reference materials (RMs) of pyrite S0302A (δ34S V-CDT = 0.0 ± 0.2‰ (Liseroudi et al., 2021)) and barite S0327 (δ34SV-CDT = 11.0 ± 0.5 ‰; δ18OV-SMOW = 21.3 ± 0.2 ‰ (Magnall et al., 2016)). Microscale isotopic analyses were carried out using Cameca IMS1280 large-geometry secondary ion mass spectrometer (SIMS) operated in multi-collector mode at the NordSIMS laboratory, Stockholm, Sweden. External analytical reproducibility (1 σ) was typically ± 0.04‰ δ34S for pyrite, ± 0.15‰ δ34S, and ± 0.12‰ δ18O for barite. The sample identification, location, and depth are reported in the data files.

Radiometric Dates from the South American Andes and Adjacent Areas: A Compilation - part 3 metamorphic rocks

A compilation of 29,574 published radiometric dates for metamorphic rocks from the South American Andes and adjacent parts of South America have been tabulated for access by researchers via GEOROC Expert Datasets. The compilation exists as a spreadsheet for access via MS Excel, Google Sheets, and other spreadsheet applications. Initial igneous compilations were utilized in two publications by the author, Pilger (1981, 1984). The compilations have been added to in subsequent years with the metamorphic and sedimentary compilations separated in the last few years. Locations in latitude and longitude are largely taken from the original source, if provided, with UTM locations maintained and converted; in some cases, sample locations were digitized from electronic maps if coordinates were otherwise not available. Analytical results are not included to prevent the files from becoming too large. The existing compilation incorporates compilations by other workers in smaller regions of the Andes. References to original and compilation sources are included. While I am updating reconstructions of the South American and Nazca/Farallon plates, incorporating recent studies in the three oceans, for comparison with the igneous dates for the past 80 m. y., it is hoped that the spreadsheets will be of value to other workers. Reliability: In most cases the data have been copy/pasted from published or appendix tables. In a few cases, the location has been digitized from published maps; the (equatorial equidistant) maps were copied into Google Earth and positioned according to indicated coordinates, with locations digitized and copied/pasted into the spreadsheet. (It is possible that published maps are conventional Mercator-based, even if not so identified, rather than either equatorial equidistant or Universal Transverse Mercator; this can be a source of error in location. For UTMs, the errors should be minor.) Duplicates are largely recognized by equivalent IDs, dates, and uncertainties. Where primary sources have been accessed, duplicate data points in compilations are deleted. (Analytic data are NOT included.) This compilation is part of a series. Companion compilations of radiometric dates from igneous and sedimentary rocks are available at https://doi.org/10.5880/digis.e.2023.005 and https://doi.org/10.5880/digis.e.2023.006, respectively.

Multi-collector 40Ar/39Ar data of glass and plagioclase from a tuff sample in the marine claystone of the Argille di Spadafora (NE Sicily, Italy)

The dataset contain full 40Ar/39Ar geochronological data completed by multi collector noble gas mass spectrometry on plagioclase and glass separates from a tuff sample interbedded in Pleistocene marine claystone (Argille di Spadafora) of northeastern Sicily (Italy). Tuff unit VU7 was identified in the field using the published base map and stratigraphic nomenclature of Di Bella et al. (2016), which correlates to bathyal marine marl (Argille di Vito Superiore) in southern Calabria. The tuff contains stratified white lapilli with abundant fresh volcanic glass shards and was deposited by a submarine turbidity current from a single volcanic eruption. The Ar laserprobe facility was realized with the financial support of CNR. The CO2 laser system was acquired within the PNRR – Mission 4, “Education and Research” - Component 2, “From research to business” - Investment line 3.1, “Fund for the creation of an integrated system of research and innovation infrastructures” - Project IR0000025 MEET. EPOS JRU Italia is acknowledged for support in the Laboratory maintenance.

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