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Mineral reflectance spectra and chemistry of 29 rare earth-bearing minerals and rare earth oxide powders including niobium- and tantalum-oxide powder

The data set contains mineral chemical analyses of 32 rare earth element (REE) -bearing minerals (REMin) and rare-earth oxides (REO) and their corresponding hyperspectral spectra. The hyperspectral data was acquired with the HySpex system in a range of 400 – 2500 nm and is presented in a spectral library. The resulting reflectance data are scaled from 0 - 10000. The two Rare Earth Element (REE) libraries consist of the spectra of 16 rare earth oxides powders (REO) and 14 REE-bearing minerals (REMin). In addition, it contains the spectra of niobium- and tantalum oxide, two elements technically not part of the REEs. The spectral library presented here is part of a bigger collection of spectral libraries including copper-bearing surface samples from Apliki copper-gold-pyrite mine (Koerting et al., 2019a, http://doi.org/10.5880/GFZ.1.4.2019.005) and copper-bearing minerals (Koellner et al., 2019, http://doi.org/10.5880/GFZ.1.4.2019.003). These libraries aim to give a spectral overview of important resources and ore mineralization.

Mineral spectra and chemistry of 37 copper bearing surface samples from Apliki copper-gold-pyrite mine in the Republic of Cyprus

The data set contains mineral chemical analyses of 37 different surface materials from the copper-gold-pyrite mine Apliki in the Republic of Cyprus and their corresponding hyperspectral spectra. The field samples were sampled in March 2018 in cooperation of the Cyprus Geological Survey Department of the Republic of Cyprus (GSD) and the German Research Centre for Geosciences (GFZ). The hyperspectral data was acquired with the HySpex system in a range of 400 – 2500nm and is presented in a spectral library. Detailed information about the mineral specimen, sample area and geochemistry is presented in the data sheets. The spectral library presented here is part of a bigger collection of spectral libraries including samples from rare-earth minerals, rare-earth-oxides (Koerting et al., 2019a, http://doi.org/10.5880/GFZ.1.4.2019.004) and copper-bearing minerals (Koellner et al., 2019, http://doi.org/10.5880/GFZ.1.4.2019.003).

Mineral spectra and chemistry of 20 copper bearing minerals

The data set contains mineral chemical analyses of 20 different copper bearing minerals and their corresponding hyperspectral spectra. The hyperspectral data were acquired with the HySpex system in a range of 400 – 2500 nm and are presented in a spectral library. Detailed information about the mineral specimen, sample area and geochemistry is presented in the data sheets and associated data description. The spectral library presented here is part of a bigger collection of spectral libraries including samples from rare-earth minerals, rare-earth-oxides (Koerting et al., 2019a, http://doi.org/10.5880/GFZ.1.4.2019.004) and field samples from a copper-gold-pyrite mine in the Republic of Cyprus (Koerting et al., 2019b, http://doi.org/10.5880/GFZ.1.4.2019.005).

Mineralogical and geochemical data of two weathering profiles in a Mediterranean and a humid climate region of the Chilean Coastal Cordillera

This publication provides mineralogical and geochemical data of two 6-m-deep weathering profiles formed from granitic rock. They are located in different climate zones (Mediterranean and humid) and are close to the national parks of La Campana and Nahuelbuta in the Chilean Coastal Cordillera. Additional rock samples from adjacent boreholes were used to relate the regolith to the bedrock. The profiles were sampled in February and March 2020 as part of the German Science Foundation (DFG) priority research program SPP-1803 “EarthShape: Earth Surface Shaping by Biota”. The goal of this project is to obtain a holistic view on the interplay of the geosphere and the biosphere under different climatic conditions and to investigate weathering mechanisms. The aim of this publication is to provide the data basis for understanding the weathering processes that control the development of the profiles in relation to different climatic conditions. To this end, we measured the geochemistry with X-ray fluorescence, extracted Fe, Al and Si with oxalate/dithionite, determined the grain sizes by wet sieving and pipetting, measured the magnetic susceptibility, and analysed the mineral content of bulk samples and clay fractions with X-ray diffraction. The data are compiled in one Excel file and all results of the X-ray diffraction measurements are available as RAW- and TXT files.

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).

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.

Geochemical data on silicon isotope and Ge/Si ratios along a global erodosequence

We provide geochemical data for three sites that define a gradient of erosion rates – an “erodosequence”. These sites are the Swiss Central Alps, a rapidly-eroding post-glacial mountain belt; the Southern Sierra Nevada, USA, eroding at moderate rates; and the slowly-eroding tropical Highlands of central Sri Lanka. Specifically, we provide silicon isotope ratios and germanium/silicon ratios and the major element composition of 1) rock, 2) saprolite, 3) soil, 4) plants, 5) river dissolved loads, 6) the soil and saprolite amorphous silica fraction (accessed with a NaOH leach), and 7) the soil and saprolite clay-size fraction (isolated with a differential settling protocol). These data serve two purposes. First, they allow us to improve understanding of the controls on silicon isotopes and germanium/silicon ratios in the 'Critical Zone'. Specifically, we can quantify the fractionation factors (for silicon isotopes) and the exchange coefficients (for germanium/silicon ratios), for secondary mineral precipitation and for biological uptake. Secondly, we can use mass-balance approaches to quantify the partitioning of silicon - a nutrient, and a major rock-forming element - among secondary minerals, plant material, and solutes. All samples are assigned with International Geo Sample Numbers (IGSN), a globally unique and persistent Identifier for physical samples. The IGSNs are provided in the data tables and link to a comprehensive sample description.

New Chilean and a global compilation of soil production, chemical weathering, and physical erosion rates from soil-mantled hillslopes

This data publication contains new and recalculated soil production, chemical weathering, and physical erosion rates for granitoid soil-mantled hillslopes in the Chilean Coastal Cordillera. For further comparison and data discussion the data publication presents global rates from granitoid soil-mantled hillslopes combined with a suite of parameters at the sample location (e.g., slope, precipitation, temperature, vegetation cover). The data were collected within the DFG Priority Program 1803 "EarthShape - Earth Surface Shaping by Biota". The data publication contains one excel table including tables S1 to S9. In addition, these nine sub-tables are available as txt files in a zip-file. They are supplementary material to Schaller et al. (2021).

Dataset on Biogeochemical cycling of Mg and Li isotopes in the Conventwald (the Black Forest, Germany)

This data set contains chemical and Mg isotope analyses of time-series creek water, subsurface flow (0-15cm and 15-150cm), vegetation, regolith, clay-sized fraction and exchangeable fraction of regolith from a catchment of the Black Forest, Germany. This dataset is a following work of “Uhlig, D., & von Blanckenburg, F. (2019)", in which major and trace elements concentrations and 87Sr/86Sr isotope data was reported on the same batch of samples. With the new Mg isotope analyses, we investigated the potential controlling factors on water Mg isotopic composition, and we found exchange reactions in our catchment are a primary control on water chemistry. To further interrogate this finding, a batch of adsorption and desorption experiments using soil samples from our study site were carried out. The adsorption and desorption experiment results are also included here. This combination of field research and lab experiments informs about processes fractionating Mg in the critical zone – with the role of the exchangeable pool highlighted as particularly important – and further verifies the potential of Mg isotopes as a tool in tracing continental weathering process. Samples are assigned with International Geo Sample Numbers (IGSN), a globally unique and persistent Identifier for physical samples.

Geochemical data on rock weathering along an erodosequence

We provide geochemical background data on the partitioning and cycling of elements between rock, saprolite, soil, plants, and river dissolved and solid loads from at three sites along a global transect of mountain landscapes that differ in erosion rates – an “erodosequence”. These sites are the Swiss Central Alps, a rapidly-eroding post-glacial mountain belt; the Southern Sierra Nevada, USA, eroding at moderate rates; and the slowly-eroding tropical Highlands of Sri Lanka. The backbone of this analysis is an extensive data set of rock, saprolite, soil, water, and plant geochemical data. This set of elemental concentrations is converted into process rates by using regolith production and weathering rates from cosmogenic nuclides, and estimates of biomass growth. Combined, they allow us to derive elemental fluxes through regolith and vegetation. The main findings are: 1) the rates of weathering are set locally in regolith, and not by the rate at which entire landscapes erode; 2) the degree of weathering is mainly controlled by regolith thickness. This results in supply-limited weathering in Sri Lanka where weathering runs to completion, and kinetically-limited weathering in the Alps and Sierra Nevada where soluble primary minerals persist; 3) these weathering characteristics are reflected in the sites’ ecosystem processes, namely in that nutritive elements are intensely recycled in the supply-limited setting, and directly taken up from soil and rock in the kinetically settings; 4) contrary to common paradigms, the weathering rates are not controlled by biomass growth; 5) at all sites we find a deficit in river solute export when compared to solute production in regolith, the extent of which differs between elements but not between erosion rates. Plant uptake followed by litter erosion might explain this deficit for biologically utilized elements of high solubility, and rare, high-discharge flushing events for colloidal-bound elements of low solubility. Our data and the new metrics have begun to serve for calibrating metal isotope systems in the weathering zone, the isotope ratios of which depend on the flux partitioning between the compartments of the Critical Zone. We demonstrate this application in several isotope geochemical companion papers with associated datasets from the same samples. All samples are assigned with International Geo Sample Numbers (IGSN), a globally unique and persistent Identifier for physical samples. The IGSNs are provided in the data tables and link to a comprehensive sample description in the internet.

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