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R-Package – Supplement to: Constraints on the role of marine authigenic clay formation in determining seawater lithium isotope composition

This publication contains the R-Package used to solve the calculations performed in Läuchli et al., (2025). The package contains a README.txt file, as well as six scripts stored in the "scripts" file including: (1) "main_script.R" running the complete Monte-Carlo simulation, (2) "calling_data.R" calling the data, (3) "isotope_signature.R" extracting the isotope signature of marine authigenic clays using the dataset presented in Läuchli et al., (submitted), (4) "global_fluxes_uncertainties_rivers.R" simulating uncertainties associated with single-data point river on global estimations of the lithium flux from discharged by rivers to seawater, (5) "global_fluxes.R" solving the ocean lithium isotope budget, and The data files necessary to solve the R-Package are provided as .csv and stored in the "csv" file. Output files are stored in the "export" file. The scripts are written for the R Software. The data were acquired as part of the German Science Foundation (DFG) priority program SPP-1803 “EarthShape: Earth Surface Shaping by Biota” initiated and lead by Friedhelm von Blanckenburg and Todd Ehlers. The GeoB cores samples were provided by the MARUM Research Center (Bremen). The 22SL Gravity Core was stored and supplied by the Bundesanstalt für Geowissenschaften und Rohstoffe (BGR, Hannover). -------------------------------------------------- Packages: The R packages devtools, dplyr, compositions, tidyr, EnvStats, gdata, and gmp were used for calculations. The R-Package was managed using packrat: compositions (Boogaart et al., 2022; License: GPL >= 2) devtools (Wickham et al., 2022; MIT License) dplyr (Wickham et al., 2022; MIT License) EnvStats (Millard, 2022; License: GPL >= 3) gdata (Warnes et al., 2022; License: GPL-2) gmp (Lucas et al., 2023; License: GPL >= 2) packrat (Ushey et al., 2022; License: GPL-2) tidyr (Wickham and Girlich, 2022; MIT License)

Differentiating between hydrothermal and diagenetic carbonates using rare earth element and yttrium (REE+Y) geochemistry: A case study from the Paleoproterozoic George Fisher massive sulphide Zn deposit

Carbonate minerals are ubiquitous in most sediment-hosted mineral deposits. These deposits can contain a variety of carbonate types with complex paragenetic relationships. When normalized to chondritic values (CN), rare-earth elements and yttrium (REE+YCN) can be used to constrain fluid chemistry and fluid-rock interaction processes in both low- and high-temperature settings. Unlike other phases (e.g., pyrite), the application of in situ laser ablation-inductively coupled plasma-mass spectroscopy (LA-ICP-MS) data to the differentiation of pre-ore and hydrothermal carbonates remains relatively untested. To assess the potential applicability of carbonate in situ REE+Y data, we combined transmitted light and cathodoluminescence (CL) petrography with LA-ICP-MS analysis of carbonate mineral phases from (1) the Proterozoic George Fisher clastic dominated (CD-type) massive sulfide deposit and from (2) correlative, barren host rock lithologies (Urquhart Shale Formation). The REE+YCN composition of pre-ore calcite suggests it formed during diagenesis from diagenetic pore fluids derived from ferruginous, anoxic seawater. Hydrothermal and hydrothermally altered calcite and dolomite from George Fisher is generally more LREE depleted than the pre-ore calcite, whole-rock REE concentrations, and shale reference values. We suggest this is the result of hydrothermal alteration by saline Cl--rich mineralizing fluids. Furthermore, the presence of both positive and negative Eu/Eu* values in calcite and dolomite indicates that the mineralizing fluids were relatively hot (>250°C) and cooled below 200-250°C during ore formation. This study confirms the hypothesis that in situ REE+Y data can be used to differentiate between pre-ore and hydrothermal carbonate and provide important constraints on the conditions of ore formation.

Quantitative mineralogy and bulk rock geochemistry of the Kupferschiefer system, Saale subasin, Eastern Germany

The Southern Permian Basin in Central Europe (in Germany and Poland) hosts several sediment-hosted Cu deposits (see Borg et al., 2012). The Cu- and Zn-Pb sulfide mineralization is preserved in the coarse-grained continental siliciclastics of the uppermost Rotliegend (S1), organic matter- and carbonate-rich marine mudstones of the Kupferschiefer (T1) and dolomitic Zechstein Limestone (Ca1). In these datasets, we provide quantitative mineralogical and geochemical data of drill core samples from the Saale Basin in East Germany. The samples include the uppermost Rotliegend sandstone (S1), Kupferschiefer (T1) and lowermost Zechstein Limestone (Ca1), referred as the Kupferschiefer system, from three drill cores (Sangerhausen, Allstedt and Wallendorf). This data publication includes quantitative mineralogy (X-ray diffraction), bulk rock major, minor and trace element geochemistry (X-ray fluorescence and inductively coupled mass spectrometry) and total organic carbon (elemental analyzer).

Sediment geochemistry data for the publication: “10Be/9Be ratios reveal marine authigenic clay formation”

As reverse weathering has been shown to impact long-term changes in atmospheric CO2 levels, it is crucial to develop quantitative tools to reconstruct marine authigenic clay formation. We explored the potential of the beryllium (Be) isotope ratio (10Be/9Be) recorded in marine clay-sized sediment to track neoformation of authigenic clays. The power of such proxy relies on the orders-of-magnitude difference in 10Be/9Be ratios between continental Be and Be dissolved in seawater. On riverine and marine sediments collected along a Chilean margin transect we chemically extracted reactive phases and separated the clay-sized sediment fraction. We compare the riverine and marine 10Be/9Be ratio of this fraction. Moreover, we compare the elemental and mineralogical composition and the Nd and Sr-isotopic composition of these samples. 10Be/9Be ratios increase four-fold from riverine to marine sediment. We attribute this increase to the incorporation of Be high in 10Be/9Be from dissolved biogenic opal, which also serves as a Si-source for the precipitation of marine authigenic clays. 10Be/9Be ratios thus sensitively track reverse-weathering reactions forming marine authigenic clays.

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