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Here we provide in situ 10Be data, meteoric 10Be data, X-Ray fluorescence data, infiltration rate field date, chemical extraction data, a summary of grain size data, all grain size data (Table S7), mineral point counting data, XRD data, soil grain size data, and data from laboratory measurements of hydrological parameters. Field work in Santa Gracia was conducted in February of the years 2019 and 2020 and laboratory work was conducted between 2019 and 2023. This data publication accompanies our study (Lodes et al., 2024), in which we investigate whether lithology controls drainage density in Santa Gracia, a semi-arid field site in Central Chile. In the study, we compare the density of drainages in two distinct, neighbouring landscapes underlain by a monzogranite and two diorite plutons (which we refer to as the “inner diorite” and the “outer diorite”). We collected multiple datasets to understand the underlying mechanisms behind the drainage density differences. The data was collected as part of the German Science Foundation (DFG) priority research program SPP-1803 “EarthShape: Earth Surface Shaping by Biota” (grant SCHE 1676/4-1 and -2 to D. S.; funding of P. G. through grant BE 1780/53-1 and -2).
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.
Cosmogenic nuclide measurements are commonly biased by weathering within the cosmogenic nuclide production zone. The code package “WeCode” (Weathering Corrections for denudation rates) integrated within the CRONUScalc v2.1 (Marrero et al., 2016) software performs weathering corrections and calculations, as well as offering pixel-by-pixel catchment production rate estimates for alluvial samples. Weathering corrections can be applied for weathering within the regolith or along the regolith-bedrock interface, as is common in carbonate bedrock. The methods for the weathering corrections are described in Ott et al. (2022). Please refer to the README for information on how to use the software. A set of input examples and scripts is provided for illustration. CRONUScalc can be downloaded here https://bitbucket.org/cronusearth/cronus-calc/src/v2.1
The Chilean Coastal Cordillera features a spectacular climate and vegetation gradient, ranging from arid and unvegetated areas in the north to humid and forested areas in the south. The DFG Priority Program "EarthShape" (Earth Surface Shaping by Biota) uses this natural gradient to investigate how climate and biological processes shape the Earth's surface. We explored the critical zone, the Earth's uppermost layer, in four key sites located in desert, semidesert, mediterranean, and temperate climate zones of the Coastal Cordillera, with the focus on weathering of granitic rock. Here, we present first results from four ~2m-deep regolith profiles to document: (1) architecture of weathering zone; (2) degree and rate of rock weathering, thus the release of mineral-derived nutrients to the terrestrial ecosystems; (3) denudation rates; and (4) microbial abundances of bacteria and archaea in the saprolite. From north to south, denudation rates from cosmogenic nuclides are ~10 t km-2 yr-1 at the arid Pan de Azúcar site, ~20 t km-2 yr-1 at the semi-arid site of Santa Gracia, ~60 t km-2 yr-1 at the mediterranean climate site of La Campana, and ~30 t km-2 yr-1 at the humid site of Nahuelbuta. A and B horizons increase in thickness and elemental depletion or enrichment increases from north (~26 °S) to south (~38 °S) in these horizons. Differences in the degree of chemical weathering, quantified by the chemical depletion fraction (CDF), are significant only between the arid and sparsely vegetated site and the other three sites. Differences in the CDF between the sites, and elemental depletion within the sites are sometimes smaller than the variations induced by the bedrock heterogeneity. Microbial abundances (bacteria and archaea) in saprolite substantially increase from the arid to the semi-arid sites. With this study, we provide a comprehensive dataset characterizing the Critical Zone geochemistry in the Chilean Coastal Cordillera. This dataset confirms climatic controls on weathering and denudation rates and provides prerequisites to quantify the role of biota in future studies. The data are supplementary material to Oeser et al. (2018). 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. The content of the eight data tables is: Table S1: Catena properties of the four primary EarthShape study areas. Table S2: Major and selected trace element concentration for bedrock samples. Table S3 Normative modal abundance of rock-forming minerals. Table S4: Major and selected trace element concentration for regolith samples and dithionite and oxalate soluble pedogenic oxides. Table S5: Weathering indices CDF and CIA, and the mass transfer coefficients (τ) for major and trace elements along with volumetric strain (ɛ). Table S6: Chemical weathering and physical erosion rates Table S7: Relative microbial abundances in saprolite of the four study areas. Table S8: Uncorrected major and trace element concentration. The data tables are provided as one Excel file with eight spreadsheets, as individual tables in .csv format in a zipped archive and as printable PDF versions in a zipped archive.
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.
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.
This dataset contains petrophysical, geochemical, and mineralogical data from a drilling core from the Coastal Cordillera, Chile. The drilling campaign in the semi-arid field site Private Reserve Santa Gracia was conducted in the framework of the “EarthShape” project (DFG SPP1803) to study deep weathering along a climate gradient. Previous studies in this area found that the weathering front is located much deeper than expected (Oeser et al., 2018). To explore the weathering profile and the depth of the weathering front, we performed various geochemical, petrophysical, and mineralogical analyses. The drilling campaign was conducted in March and April 2019, using the wireline drilling method with a standard industry truck-mounted PQ3-sized (85 mm core diameter, 123 mm hole diameter) rotary drilling rig (Sondajes Araos E.I.R.L.). A detailed description of the drilling activities is given in Krone et al. (2021). The retrieved core runs with a maximum length of 1.5 m were drilled using potable water, with added contamination control tracer for further microbiological analyses of the rock. As basis for our detailed study of deep weathering we determined the porosity, density, specific surface area, elemental composition, mineralogical composition, Fe oxidation, and the degree of weathering from chemical depletion, volumetric strain, and the weathering rate using the in situ cosmogenic nuclide beryllium-10 (10Be).
This data publication contains mineralogical, geochemical and magnetic susceptibility data of an 87.2 m deep profile of hydrothermally altered plutonic rock in a semi-arid region of the Chilean Coastal Cordillera (Santa Gracia). The profile was recovered during a drilling campaign (March and April 2019) as part of the German Science Foundation (DFG) priority research program SPP-1803 “EarthShape: Earth Surface Shaping by Biota” which aims at understanding weathering of plutonic rock in dependency on different climatic conditions. The goal of the drilling campaign was to recover the entire weathering profile spanning from the surface to the weathering front and to investigate the weathering processes at depth. To this end, we used rock samples obtained by drilling and soil/saprolite samples from a manually dug 2 m deep soil pit next to the borehole. To elucidate the role of iron-bearing minerals for the weathering, we measured the magnetic susceptibility, determined the mineral content and analysed the geochemistry as well as the composition of Fe-bearing minerals (Mössbauer spectroscopy) in selected samples.
The data herein were used to trace the source and depth of nutrient uptake in two mountainous temperate forest ecosystems in southern Germany (Conventwald/Black Forest and Mitterfels/Bavarian Forest). Presented are phosphorus (P) concentrations from various P fractions of soil, saprolite, weathered bedrock and unweathered bedrock samples from drilling cores (depth: 20 m, site Conventwald (CON), and 30 m, site Mitterfels (MIT)) obtained by sequential extractions following the Hedley fractionation method. Further, the dataset contains strontium (Sr) and beryllium (Be) isotope data from drilling cores mentioned above. 87Sr/86Sr data are provided for bulk samples of forest floor, soil, saprolite, weathered bedrock, and unweathered bedrock. For soil and saprolite samples, additional Sr isotope ratios of the water-soluble and the exchangeable Sr fractions are provided. 87Sr/86Sr, beryllium concentrations (measured by Quadrupole-ICP-MS) and 10Be(meteoric)/9Be data from living leaves, needles, and stem wood (heartwood and sapwood of Fagus sylvatica and Picea abies) from both study sites are reported. Beryllium concentrations (measured by ICP-OES) and isotope ratios of amorphous oxides sequentially extracted from soil and saprolite at CON and MIT are provided. Soil pH at CON and MIT is also provided. Compiled concentrations of K, Ca, Mg and P and total deposition rates of atmospheric dust deposition are also included in the dataset. The data presented here stem from sampling campaigns and analyses described in Uhlig et al. (2020) to which they are supplementary material to. Samples were mainly processed in the Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES), the University of Bonn (P Hedley fractionation) and the University of Cologne - Centre for Accelerator Mass Spectrometry (AMS) (10Be measurements). Tables supplementary to the article, including data quality control, are provided in pdf and xls formats. In addition, data measured in the course of the study are also provided as machine readable ASCII files. All samples are indexed with an International Geo Sample Number (IGSN). Sample metadata can be viewed by adding the IGSN to the “http://igsn.org/” URL (e.g. igsn.org/GFDUH00LT).
With this data, we expand the data set characterizing the Critical Zone geochemistry along the Chilean Coastal Cordillera provided by Oeser et al. (2018). This data set completes the results of bulk geochemical analysis of bedrock and regolith with those of bulk analysis of major plants and those of the bio-available fraction in saprolite and soil (determined using a modified sequential extraction method on bulk regolith samples after Arunachalam et al., 1996;He et al., 1995;Tessier et al., 1979). For all those compartments of the Earth’s Critical Zone, we further present radiogenic (87Sr/86Sr) and stable (δ88/86Sr) strontium isotope ratios. A detailed graphical presentation and discussion of this data as well as method description is given in Oeser and von Blanckenburg, (2020a): Do degree and rate of silicate weathering depend on plant productivity? and Oeser and von Blanckenburg, (2020b): Strontium isotopes trace biological activity in the Critical Zone along a climate and vegetation gradient. Using this data, we were thus, able to determine weathering rates and nutrient uptake along the “EarthShape” climate and vegetation gradient in the Chilean Coastal Cordillera and to identify the sources of mineral nutrients to plants. Ultimately, we were able to budget inventories, gains and losses of nutritive elements in and out of these ecosystems and to quantify nutrient recycling. We found that the weathering rate does not increase from north to south along the climate gradient. Instead, the increase in biomass growth rate is accommodated by faster nutrient recycling. Instead, the increase in biomass nutrient demand is accommodated by faster nutrient recycling. In the absence of an increase in weathering rate despite a five-fold increase in precipitation and NPP, we hypothesize that plant growth might in fact dampen weathering rates. Radiogenic and stable Sr isotopes in combination with mass balance calculations were used to detect the Sr sources and quantify its fluxes in four ecosystems along the “EarthShape” climate and vegetation gradient. Estimated whole-plant Sr isotope compositions reveal a preferential uptake of light Sr from soil solution and subsequent export of fractionated organic material from the ecosystems. This export correlates well with erosion rate E and potentially impairs the ability for direct Sr acquisition from solid plant debris and thus reduces the recycling factor of Sr and possibly Ca and that of other mineral nutrients, too. 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. Tables included in this data publication: Table S1: Chemical composition, radiogenic strontium (87Sr/86Sr), stable strontium (δ88/86Sr), and molar Ca/Sr ratios of representative bedrock samples from Pan de Azúcar, Santa Gracia, La Campana, and Nahuelbuta Table S2: Weathering indices CDF and τ, radiogenic strontium (87Sr/86Sr), stable strontium (δ88/86Sr), and molar Ca/Sr ratios of the 2 × 4 regolith profiles. Table S3: Concentration of the bio-available fraction, comprised of the water-soluble and the exchangeable fraction. Table S4: Concentration of the water-soluble and the exchangeable fraction, and the relative amount of the bio-available fraction (pooled water-soluble and exchangeable fraction) on bulk regolith. Table S5: Chemical composition of the study sites’ single plant organs along with their respective radiogenic strontium (87Sr/86Sr), stable strontium (δ88/86Sr), and molar Ca/Sr ratios
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