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  • These data were collected to study oxidative weathering processes in the Waiapu River catchment, New Zealand, with potential carbon release sourced from the oxidation of petrogenic organic carbon or carbonate dissolution coupled to the oxidation of sulfide minerals. There, in mudstones exposed in a highly erosive gully complex, in situ CO2 emissions were measured with drilled gas accumulation chambers following the design by Soulet et al. (2018, Biogeosciences 15, 4087-4102, https://doi.org/10.5194/bg-15-4087-2018). Temporal and spatial variability in CO2 flux can be put in context with environmental changes (e.g., temperature and hydrology). For this, CO2 release from 5 different chambers, which were installed over a transect of ~ 10 m length in a gully above a nearby streambed, was measured several times over a short study period (circa one week). In addition, the gaseous CO2 storage (partial pressure) in the shallow weathering zone was measured prior to a CO2 flux measurement. To understand the source of CO2, gas samples were collected and their stable and radioactive carbon isotope compositions determined. In this process, we identified a contaminant, which was associated with the chamber installation, that can be traced in the gas samples that were collected within 4 days following the installation. Details of the subsequent data analysis and interpretation can be found in: Roylands et al. 2022, Chemical Geology: Capturing the short-term variability of carbon dioxide emissions from sedimentary rock weathering in a remote mountainous catchment, New Zealand. This work was supported by the European Research Council (Starting Grant to Robert G. Hilton, ROC-CO2 project, grant 678779).

  • The data deposit includes results from 12 experiments that reacted carbon dioxide, seawater and limestone as a method of CO2 sequestration (as xlsx files). The data were obtained by Dr Huw Pullin, Cardiff University as part of a UKRI funded research project. Experiments were conducted under controlled temperatures (20degC), and CO2 pressures (5 and 50% v/v at 1 atm). The methods used are described in Xing et al., 2022 Chemical Engineering Journal. 431. 134096 DOI: 10.1016/j.cej.2021.134096

  • These data accompany a manuscript, titled: Stream and Slope Weathering Effects on Organic-rich Mudstone Geochemistry and Implications for Hydrocarbon Source Rock Assessment: A Bowland Shale Case Study All files with prefix 'Man_1' relate to this submission. The manuscript was submitted to the journal Chemical Geology in December 2016. Data include: 1) A range of photographs from the outcrop, drill cores, sub-samples, 'weathering grades' and thin section microphotographs from the Bowland Shale; 2) The results of mineralogical (whole rock powder x-ray diffraction; XRD) analyses for 18 subsamples; 3) The results of inorganic geochemical analyses (LECO elemental C and S, x-ray fluorescence major and trace elements) for 18 subsamples; 4) The results of organic geochemical analyses (Rock-Eval pyrolysis, d13Corg) for 20 subsamples; 5) RStudio scripts used to conduct statistical analyses (e.g., Principal Components Analysis) and generation of figures.

  • The measurements and data contained here were obtained to study the chemical weathering of sedimentary rocks, and more specifically the oxidation of rock organic carbon and the associated release of CO2. The primary aim was to better understand the production and mobility of the trace element rhenium during weathering, because this element has been proposed as a proxy for rock organic carbon oxidation. The study focused on three Alpine catchments that drain sedimentary rocks, which all experience moderate to high erosion rates where oxidative weathering rates are thought to operate faster. Two catchments were located in Switzerland - the Erlenbach and Vogelbach, and one catchment in Colorado, USA - the East River. To study chemical weathering and the production and mobility of rhenium, a suite of samples were collected to capture the source and products of weathering reactions. These focused on stream and river water, river sediments and weathering profiles collected on sedimentary rocks. The Swiss catchments, water samples were collected from 2011 and 2012 to capture changes in river flow and seasonal changes in hydro-climate. Samples were collected from a gauging station operated by the Swiss Federal Institute for Forest, Snow and Landscape Research - WSL. In the East River, samples were collected from the gauging station operated by the Lawrence Berkeley National Laboratory Watershed Function Scientific Focus Area from 2015 and 2016. Additional samples included snow samples collected from the Erlenbach. All water samples were analysed for their major dissolved ion content by Ion Chromatography. Dissolved rhenium concentrations were determined by High Resolution and Quadrupole Inductively Coupled Plasma Mass Spectrometry. Solid samples were digested and analysed for Re content by ICP-MS. These geochemical measurements were paired with water discharge data to quantify the flux of dissolved elements, using rating curves and flux-weighted average methods, and interpret the hydrological context of ion production and mobility through the landscape. This new data acquisition was funded by a European Research Council Starting Grant to Robert Hilton (ROC-CO2 project, grant 678779) and a Natural Environment Research Council (NERC), UK, Standard Grant (NE/I001719/1). Further details of subsequent data analysis and interpretation can be found in Hilton, R.G., et al., 2021, Concentration-discharge relationships of dissolved rhenium in Alpine catchments reveal its use as a tracer of oxidative weathering, Water Resources Research

  • This spreadsheet contains 21 oxygen isotope measurements for hematite and mixed hematite/goethite samples from the supergene profiles of the Spence and Cerro Colorado porphyry copper deposits in the Central Andes. Columns are also included which contain calculated isotopic values for weathering fluids which were present at the time of iron oxide formation. These data are presented and discussed in the G-cubed paper 'A rusty record of weathering and groundwater movement in the hyperarid Central Andes' (Shaw et al., 2021). Weathering fluid isotopic values are calculated using the published fractionation factors of Clayton & Epstein (1961), Yapp (1990) and Bao & Koch (1999). The authors have the most confidence in the fluid values obtained using the fractionation factor of Yapp (1990), for reasons outlined in the publication.

  • This spreadsheet contains (U-Th-Sm)/He data for 73 hematite samples from the supergene profile of the Spence porphyry copper deposit in the Central Andes. These data are discussed in the G-cubed publication titled 'A rusty record of weathering and groundwater movement in the hyperarid Central Andes' (Shaw et al., 2021). Spence porphyry copper deposit Drill hole SPD0324, UTM WGS1984 19S, E 474975.22, N 7481100.39 Drill hole SPD 1848, UTM WGS1984 19S, E 474998.29, N 7481399.87 Drill hole SPD 0402, UTM WGS1984 19S, E 473969.87, N 7479755.01