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Shell geochemistry and environmental instability along the Georgia Coast during the Late Archaic Period (5000 - 3800 BP)
This dataset includes stable oxygen isotope (δ18O) data collected from eastern oysters (n=19) (Crassostrea virginica) and hard clams (n=59) (Mercenaria spp.) from the Late Archaic (ca. 50000-3500 cal. BP) Sapelo Shell Rings on Sapelo Island, Georgia. A total of 1064 isotope samples were collected and analyzed from these shells. The data are part of a larger project reconstructing paleo-climate and Native American adaption and resilience in the context of climate instability along the South Atlantic coast of North America during the Late Archaic Period. Shell isotope samples were collected by multiple researchers over the last decade. Carey Garland added to and cleaned the data between June 2020 and December 2021. The dataset was structured to include site name, location, and provenience (e.g., unit, level, etc.) associated with each shell analyzed, as well as all raw isotope data. The original database contains sensitive information, such as the specific location of archaeological sites. If a professional archaeologist needs site location information, they can contact the Georgia Archaeological Site File.
Geochemistry of soils and eroded suspended sediments from two large rural catchments in southern Brazil for studies on Suspended Sediment Fingerprinting
<p> <strong>1. Introduction</strong></p> <p>This dataset comes from a research project entitled "Water and pollutants, from cropfields to cities: evaluation and improved of soil management technologies in a catchment network " supported by the Foundation for Research Support of the State of Rio Grande do Sul (FAPERGS) and National Council for Scientific and Technological Development (CNPq) (process n°10/0034-0). The project was carried out between 2010 and 2014 under the coordination of José Miguel Reichert and Danilo Rheinheimer dos Santos, professors at the Federal University of Santa Maria. One of the aims of this project was to understand the main pollutant transfer process from hillslopes to fluvial systems in large rural catchments representative of the agricultural production system in Southern Brazil. In this context, the Suspended Sediment Fingerprinting (SSF) was extremely useful for quantifying the origin of the sediment yield monitored at the outlet of these catchments. Among the various works carried out in this project, we highlight Tales Tiecher's doctoral thesis (Tiecher, 2015) that explored the SSF in many catchments, including the Conceição and Guaporé river basins.</p> <p><strong>2. Material and Methods</strong></p> <p>The catchments represent the magnitude of erosive and hydrological processes representative of Southern Brazil. The Conceição catchment has a drainage area of 804 km<sup>2</sup> (28°27′22″S and 53°58′24″ W). According to Köppen, the climate is Cfa type, with an annual rainfall between 1,750 and 2,000 mm. Geology is riodacithe basalt, with a formation of deep and highly weathered soils (Oxisols, Ultisols, and Alfisols). The relief is characterized by gentle slopes (6–9 %) on top and hillside slopes and higher steepness (10–14%) near the drainage channels. Farming based on the production of soybeans (<em>Glycine max</em>) in summer and wheat (<em>Triticumspp.</em>), oats (<em>Avena strigosa</em>), and ryegrass (<em>Lolium multiflorum</em>) in winter. The Guaporé catchment has a drainage area of 1,980 km<sup>2</sup> (28°54′41″S and 51°57′10″W), it covers part of the meridional plateau border. The climate is classified as Cfa, with annual rainfall varies between 1,400 and 2,000 mm. Geology is characterized by volcanic lava flows, and topography is undulating to hilly. Due to variations in landscape, several classes of soils (Entisols, Luvisol, Cambisol, Oxisol, Ultisol, and Chernosol). The land use is highly heterogeneous. In the upper third of the catchment, there is a predominance of soybean cultivated under no-tillage soil management. In the other two-thirds (middle and lower parts), land use and soil management are very heterogeneous. The main land uses are tobacco (<em>Nicotiana tabacum</em>) and maize (<em>Zea mays</em>) crops, Eucalyptus (<em>Eucalyptus</em> spp.), as well as pastures for dairy cattle. The contribution of unpaved roads is relevant to the sediment yield in both catchments (Didoné et al., 2014). Composite samples of potential sediment sources (cropland, unpaved roads, and stream channel banks) were collected. Sediment source samples were taken from the surface soil layer (0–0.05 m) of cropland and unpaved roads and on exposed sites located along the river channel network. Each sample was composed of at least 10 subsamples. To obtain representative samples of suspended sediment transported in the catchment’s outlet were used three strategies: (1) to collect flood suspended sediments (FSS) through the manual sampling (USDH-48) at different periods during the rising and falling stages of floods; (2) to deploy time-integrated suspended sediment samplers (TISS), by installing the device developed by Phillips et al. (2000) at different sites within the catchments; to collect fine-bed sediment (FBS) with a suction stainless sampler limiting the loss of fine material at the bed river. Source and sediment samples were oven‐dried at 50 °C, gently disaggregated using a pestle and mortar, and then sieved to 62,5 μm. The geochemical tracers evaluated were total organic carbon estimated by wet oxidation (K<sub>2</sub>Cr<sub>2</sub>O<sub>7</sub> + H<sub>2</sub>SO<sub>4</sub>) and the total concentration of Al, Ba, Be, Ca, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V, and Zn using inductively coupled plasma optical emission spectrometry after microwave‐assisted digestion with concentrated HCl and HNO<sub>3</sub> (ratio 3:1) for 9.5 min at 182 °C (Tiecher, 2015; Tiecher et al. 2017, 2018).</p> <p> <strong>3. Final remarks</strong></p> <p> The SSF results provided by this dataset (Tiecher, 2015) combined with sediment yield monitoring were very important for the assessment and modeling studies in these two catchments that took place after that (Didoné et al., 2015; 2017). In addition, other studies have explored the same sample bank, expanding upon the array of tracer properties and increasing our understanding about the mechanisms of sediment and pollutant transfer in these catchments (Le Gall et al. 2017; Zafar et al., 2017; Ramon et al., 2020).</p> <p> <strong>4. References</strong></p> <p> Didoné, E. J., Minella, J. P. G., Reichert, J. M., Merten G. H., Dalbianco, L., Barros, C. A. P., Ramon, R. (2014) Impact of no-tillage agricultural systems on sediment yield in two large catchments in southern Brazil. J Soils Sediments 14:1287–1297.</p> <p>Didoné, E.J., Minella, J.P.G., Evrard, O. (2017). Measuring and modelling soil erosion and sediment yields in a large cultivated catchment under no-till of Southern Brazil. Soil Tillage Res. 174, 24-33. https://doi.org/10.1016/j.still.2017.05.011</p> <p>Didoné, E. J.; Minela, J. P. G.; Merten, G. H. (2015). Quantifying soil erosion and sediment yield in a catchment in southern Brazil and implications for land conservation. J. Soils Sediments 11, 2334-2346. https://doi.org/10.1007/s11368-015-1160-0</p> <p>le Gall, M., Evrard, O., Dapoigny, A., Tiecher, T., Zafar, M., Minella, J. P. G., Laceby, J. P., & Ayrault, S. (2017). Tracing sediment sources in a subtropical agricultural catchment of southern Brazil cultivated with conventional and conservation farming practices. Land Degradation and Development, 28(4). https://doi.org/10.1002/ldr.2662</p> <p>Ramon, R., Evrard, O., Laceby, J. P., Caner, L., Inda, A. v., Barros, C. A. P., Minella, J. P. G., & Tiecher, T. (2020). Combining spectroscopy and magnetism with geochemical tracers to improve the discrimination of sediment sources in a homogeneous subtropical catchment. Catena, 195, 104800. https://doi.org/10.1016/j.catena.2020.104800</p> <p>Tiecher, T. (2015). Fingerprinting sediment sources in agricultural catchments in Southern Brazil. Doctoral Dissertation in Soil Science. Universidade Federal de Santa Maria, Santa Maria, RS.</p> <p>Tiecher, T., Minella, J. P. G., Caner, L., Evrard, O., Zafar, M., Capoane, V., le Gall, M., & Santos, D. R. D. (2017). Quantifying land use contributions to suspended sediment in a large cultivated catchment of Southern Brazil (Guaporé River, Rio Grande do Sul). Agriculture, Ecosystems and Environment, 237. https://doi.org/10.1016/j.agee.2016.12.004</p> <p>Tiecher, T., Minella, J. P. G., Evrard, O., Caner, L., Merten, G. H., Capoane, V., Didoné, E. J., & dos Santos, D. R. (2018). Fingerprinting sediment sources in a large agricultural catchment under no-tillage in Southern Brazil (Conceição River). Land Degradation and Development, 29(4). https://doi.org/10.1002/ldr.2917.</p> <p>Zafar, M., Tiecher, T., Capoane, V., Troian, A., dos Santos, D.R. (2017). Characteristics, lability and distribution of phosphorus in suspended sediment from a subtropical catchment under diverse anthropic pressure in Southern Brazil. Ecol. Eng. 100, 28–45.</p>
Northeastern TIME Lakes Dragonfly Mercury and supporting lake geochemistry
We sampled lake water and dragonfly larvae in 74 northeastern US lakes (TIME, or Temporally Integrated Monitoring of Ecosystems, lakes) that are part of the US EPA Long-Term Monitoring Network. The lakes are a statistical population of acid-sensitive lakes, a subset of US EPA EMAP lakes originally sampled in the early 1990s (Stoddard et al. 1996). The TIME lakes are 45 lakes in New York, 43 of which are in the Adirondacks, plus 29 lakes in New England. All lakes were sampled in a late-summer index period during 2012; lake water samples were collected manually from the epilimnion via boat, and dragonfly larvae were collected near shore using dip nets. Major ions, acid-base chemistry, total mercury and methylmercury in lake water, and total mercury and methylmercury in dragonfly larvae were analyzed. GIS analysis of lake watersheds and integration of selected EMAP-derived characteristics provides landscape and some morphometry variables for each lake. Additional annual geochemistry data for the lakes beginning in 1992 (with EMAP sampling) and ending in 2016 are available through US EPA.
Dust geochemistry and lead isotopes along an urban-rural transect in central Ohio, 2021
This data package contains geochemical concentrations and stable lead isotope ratios for dust samples collected along an urban-rural land use gradient in central Ohio during 2021. The purpose of the study was to characterize the geochemical and isotopic signatures of dust in relation to different land uses, to see how much dust varies across land use and by season. At four sites along an urban-rural transect in central Ohio, we collected weekly bulk deposition samples and analyzed the geochemical composition (47 elements including major elements, trace metals, and rare earth elements) and stable lead isotopes (208Pb, 207Pb, 206Pb, and 204Pb) of the particulate matter. This study demonstrates the tight connection between land use and anthropogenic dust composition in a region where land use is changing rapidly as development encroaches into farmland. This dataset is complete and will not be updated.
Geochemistry of a weathering profile and natural waters in the upland Mediterranean catchment of Sapine, Mt-Lozère, southern France
<p>This publication reports geochemical data from an instrumented catchment of the Service National d’Observation “Observatoire Hydro-Météorologique Cévennes-Vivarais” (OHMCV) and of the National Research Infrastructure “Observatoires de la Zone Critique: Applications et Recherche” (OZCAR) of the French “Centre National de la Recherche Scientifique” (CNRS).</p> <p>The presented data are originally contained in Kuessner, M.L. (2018). The interplay between chemical weathering and hydrology in the Critical Zone - insight from trace elements and lithium isotopes [Doctoral dissertation, Institut de Physique du Globe de Paris]</p> <p>Contents</p> <p>Table SC1. Analyses of soil samples in Sapine Creek</p> <p>Table SC2. Analyses of rock samples in Sapine Creek</p> <p>Table SC3. Analyses of rain samples in Sapine Creek and Cloutasse catchments</p> <p>Table SC4. Analyses of stream samples in Sapine Creek</p> <p>Table SC5. Analytical limits for quadrupole ICP-MS measurements</p> <p>Table SC6. Analyses of reference materials for isotope measurements</p>
Northeastern Mountain Ponds Geochemistry Compilation 1978-2019
We compiled geochemical data from published, peer-reviewed sources, gray literature, online datasets, unpublished researcher datasets, and our own data from high-elevation ponds and small lakes. Mountain ponds were defined as lakes and ponds situated at elevation >500 m (460 m in the Berkshires), and ponds surface area <60 ha. Many of our data sets are part of the US EPA LTM (Long-Term Monitoring) Network and its predecessor projects (e.g., Maine HELM, ELS-II, various scoping efforts for LTM), and state data repositories. We queried data providers and EPA staff about mountain ponds datasets in the region. We defined the region of interest (“the northeastern US”) as the Northern Appalachian Region, plus the Adirondack Mountains in New York State, ranging from latitude 42◦–46◦ north and longitude 75◦–69◦ west. We classified ponds into their respective mountain regions within Level II Ecoregion 58 – Northern Highlands, within Eastern Temperate Forest: Western Mountains (Maine’s Mahoosuc and White Mountains, to the terminus of the Appalachian Trail in Baxter State Park); White Mountains (in New Hampshire); Green Mountains (in Vermont); Berkshires (Western Massachusetts), and Adirondacks (in Adirondack Park, NY), to aid in sub-regional comparisons and statistical trend analyses.
Summer 2017 porewater and sediment geochemistry data at Second Creek, a sulfate-impacted riparian wetland in northeast Minnesota
Water and sediment chemistry data were collected over the summer and fall of 2017 at Second Creek, a riparian wetland study site near Aurora, MN, to understand sulfur and methane processes. Porewaters were collected with two distinct methods “peepers” (multi-chambered equilibrium dialysis samplers) that allow for high vertical resolution but 2-3 week averaged temporal resolution, and rhizon samplers that enable instantaneous temporal resolution but have lower spatial resolution. Porewaters were analyzed for dissolved cations, anions, sulfide, methane, iron(II)/iron(III), and pH. Sediment cores were analyzed for acid volatile sulfide, and sulfur and iron speciation via X-ray absorption spectroscopy.
Soil geochemistry and microbial community data from glaciated and potential glacial refugia sites in the McMurdo Dry Valleys, Antarctica (1993-2019)
A study was conducted to examine soil microbial communities and associated geochemical parameters at potential glacial refugia and glaciated control sites throughout the McMurdo Dry Valleys region of Antarctica. Soil samples were collected as part of ongoing long-term monitoring efforts by the McMurdo Dry Valleys Long Term Ecological Research program (MCM LTER). The oldest samples used in this study were collected during the 1993-1994 austral summer, and the newest from the 2018-2019 austral summer. "Refugia" sites were selected based on geographical positions and elevations indicative of potential glacial refugia status. Each refugia site was paired with a lower elevation "glaciated" site in the same dry valley that was not likely to have functioned as a refugium. Six replicate soils per sampling site were sequenced with 16S primers following Earth Microbiome Project protocols, filtered using the DADA2 pipeline, and clustered to amplicon sequence variant using the SILVA reference database to generate the microbial classification table included herein. Soil samples were also analyzed for various geochemical parameters as part of this study, which include P, K, NO3-, gravimetric water content, percent organic matter, pH, and electroconductivity.
Major and trace bulk sample and micro-XRF geochemistry, carbon and oxygen stable isotope compositions of magmatic and sedimentary rocks from Hovedøya Island, Oslo fjord, Norway.
<p>This data set reports on the methodologies and results of geochemical analysis carried out on samples of magmatic rock, calcite and sedimentary rocks of Hovedoya Island, Oslo fjord, Norway, in the framework of the publication by Poppe et al. (2020; <em>Geochemistry, Geophysics, Geosystems</em>; <a href="https://doi.org/10.1029/2019GC008685">https://doi.org/10.1029/2019GC008685</a>). The major and trace element bulk sample geochemical analysis was carried at the Laboratoire G-Time, Université Libre de Bruxelles, Brussels (V. Debaille), the micro-XRF mapping and line scanning, was carried out at the laboratory of the Analytical and Environmental Geo-Chemistry (AMGC) group at the Vrije Universiteit Brussel (VUB), Brussels (N.J. de Winter, S. Poppe) and the stable isotope composition analysis was carried out as well at the AMGC laboratory (S. Poppe, S. Goderis), supervised by P. Claeys and M. Kervyn, in collaboration with P. Boulvias. Data sheets are provided in .csv or .xlsx format and compressed folders containing .TIF images of µXRF elemental maps are attached. This data set also contains the complete data sets obtained for the construction of calibration curves for µXRF line scan analysis of rock samples of magmatic composition at the AMGC laboratory at VUB.</p>
Supplemental Tables for Wheat et al 2022 submitted to Geochemistry, Geophysics, Geosystems
<p>Data are from multiple expeditions to the eastern flank of the Juan de Fuca Ridge off the coast of Washington, USA. Most of the data are from the RetroFlux Expedition. These data were coupled with other published data to assess chemical conditions of the basaltic aquifer below the seafloor within the norther portion of the Juan de Fuca Plate. This work will be published in Geochemistry Geophysics Geosystems in 2022.</p>
Fig. 7 in Chaetognath grasping spines from the Devonian of Poland: their structure and geochemistry
Fig. 7. Back scattered electron images of thin section made of Devonian Phakeloides polonicus gen. et sp. nov. spines from the upper Famennian, Ostrówka Quarry, Holy Cross Mountains, Poland. A. Longitudinal section of the spine showing the apatite phases of similar density of the middle and inner layers, ZPAL Cg. 2/Ost-Ch.48. B. Longitudinal section of the spine showing the apatite phases of similar density of the middle and inner layers as well as a thin cortex of slightly higher density, which may represent fragmentarily preserved outer layer, ZPAL Cg. 2/Ost-Ch.49.
Fig. 5 in Chaetognath grasping spines from the Devonian of Poland: their structure and geochemistry
Fig. 5. Transmitted light (A1, B1) and hot cathodoluminescence images (A2, B2) of Devonian Phakeloides polonicus gen. et sp. nov. grasping spine A, ZPAL Cg. 2/Ost-Ch.41) and Polygnathus sp. conodont element (B, ZPAL Cg. 2/Ost-C.45) from the upper Famennian, Ostrówka Quarry, Holy Cross Mountains, Poland. A2, weak to moderate red cathodoluminescence of the grasping spine and bright luminescence of some parts of its outermost rim area. B2, very weak yellow-red luminescence of conodont albid tissue and non-luminescent hyaline tissue.
Fig. 1 in Chaetognath grasping spines from the Devonian of Poland: their structure and geochemistry
Fig. 1. Geographical location (A) and simplified geologic map (B) of the Holy Cross Mountains with location of the studied exposure. C. Cross-section through the ledge of the Ostrówka Quarry. 1, peritidal carbonates (Kowala Formation); 2, condensed crinoidal-cephalopod limestone beds; 3, clay with limestone intercalations; 4, black radiolarian shale (Zaręby Beds); 5, carbonate gravity flows (after Szulczewski et al. 1996).
Fig. 4 in Chaetognath grasping spines from the Devonian of Poland: their structure and geochemistry
Fig. 4. Scanning electron microscope images of Devonian chaetognath grasping spines Phakeloides polonicus gen. et sp. nov. (A–D) and conodont elements (E) from the upper Famennian, Ostrówka Quarry, Holy Cross Mountains, Poland. A. ZPAL Cg. 2/Ost-Ch.31, cross-section throughout the spine showing massive mineral structure of the middle layer characterized by the conchoidal fracture, a reticular ornamentation of the surface of the middle layer is partially visible. B. ZPAL Cg. 2/Ost-Ch.32, longitudinal section throughout the spine showing a massive mineral structure characterized by uneven fracture, which is superimposed on minor breaks forming the second-order cleavage plane. A thin, cylindrical internal layer composed of finegrained calcium phosphate crystals is visible in the innermost portion of the spine wall, around the internal cavity. C. ZPAL Cg. 2/Ost-Ch.33, a surface of the middle layer of the spine showing oblique to the spine axis, primary fibrils, visible at its slightly, broken part, and less noticeable surface striations of the reticular ornamentation. D. ZPAL Cg. 2/Ost-Ch.34, D1, cross-section throughout the spine showing porous internal zones of the middle layer, which are divided by solid cylindrical zones, a thin, cylindrical internal layer is visible in the innermost portion of the spine wall; D2, three layers in the wall of the basal portion of the spine: a thin, most internal, layer (a), the middle layer (b), and the outer layer (c). E. ZPAL Cg. 2/Ost-C.38, cross-section throughout Polynodosus sp. conodont element showing innermost pillar-like structure of densely packed, weakly lamellar, albid (white matter) tissue, and outer hyaline tissue composed of oblique apatite lammelae. The outermost portion of the conodont element consists of paralamellar variety of the hyaline tissue of more chaotic structure.
Figure 5 in Organic geochemistry of a high-latitude Lower Cretaceous lacustrine sediment sample from the Koonwarra Fossil Beds, South Gippsland, Victoria, Australia
Figure 5: Partial m/z 178, 202 and 228 mass chromatograms showing the distribution of common polycyclic aromatic hydrocarbons (PAH) in the aromatic fraction.
Figure 4 in Organic geochemistry of a high-latitude Lower Cretaceous lacustrine sediment sample from the Koonwarra Fossil Beds, South Gippsland, Victoria, Australia
Figure 4: Partial m/z 191 and 217 mass chromatograms used in calculation of sterane/hopane ratio. A ratio of 0.03 indicates that a very significant proportion of overall biomass in the lake was derived from bacteria.
Figure 2 in Organic geochemistry of a high-latitude Lower Cretaceous lacustrine sediment sample from the Koonwarra Fossil Beds, South Gippsland, Victoria, Australia
Figure 2: An uncommon example of disarticulation of a fish carcass, collected during an excavation of the Koonwarra Fossil Beds led by Tom Rich in 2013. This specimen was collected approximately 5 m from the bottom of the unit (defined here as the first> 20 cm thick unit of green siltstone/mudstone; the underlying rocks are predominantly cross-bedded, fluviatile arkosic sandstone).
Figure 3 in Organic geochemistry of a high-latitude Lower Cretaceous lacustrine sediment sample from the Koonwarra Fossil Beds, South Gippsland, Victoria, Australia
Figure 3: Saturate fraction total ion chromatogram and m/z 85 mass chromatogram showing distribution and relative abundances of n-alkanes and isoprenoids pristane and phytane.
Figure 1 in Organic geochemistry of a high-latitude Lower Cretaceous lacustrine sediment sample from the Koonwarra Fossil Beds, South Gippsland, Victoria, Australia
Figure 1: Location of the Lower Cretaceous Koonwarra Fossil Beds in South Gippsland, Victoria, Australia
Supporting Information for "Geochemistry constrains global hydrology on Early Mars"
<p>Copy of the Supporting Information for "Geochemistry constrains global hydrology on Early Mars", by Edwin S. Kite and Mohit Melwani Daswani.</p>
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Allen Brain Atlas
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