Filters: Tags: {"type":"USGS Scientific Topic Keyword","name":"geochemistry"} (X) > partyWithName: U.S. Geological Survey (X)
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Acetylene fermentation assays, nitrogen fixation assays, and growth studies were performed with Pelobacter sp. strain SFB93 and Pelobacter acetylenicus DSM3246. Data includes concentrations of acetylene and ethylene over time, and growth measured with OD680 and cell counts.
Temporal and spatial sources of silica for chert remain poorly constrained. Modern sources to the worlds oceans include silica in rivers > aeolian (dust) deposition > sea floor vents and submarine weathering. However, changes in aridity and dust flux during the Phanerozoic may explain variations in the ocean silica cycle and times and places of chert formation. The chemistry of fine quartz dust (FQD) provides a chemical mechanism for the transformation of FQD to polymorphs of silica in chert; FQD is readily dissolved, then reprecipitated as Opal-A by either biotic or abiotic processes. An unequivocal relation between increases in dust flux and biogenic opal-A in the western Pacific Ocean during the past 200 kyr...
The table contains oxide and cation compositions of olivine grains from drill core of the Duluth Complex, Minnesota. The oxides were determined by electron probe microanalysis (EPMA) and are reported in weight percent (wt%). The cations were calculated based on the oxide compositions and are reported in mole percent (mol%). Olivine is a magnesium iron orthosilicate mineral with the formula (Mg2+, Fe2+)2SiO4. Olivine forms a solid solution series with magnesium (Mg) at one end and iron (Fe) at the other. Forsterite (Mg2SiO4) is the magnesium endmember and fayalite (Fe2SiO4) is the iron endmember. Minor elements can substitute into the crystal structure, such as manganese (Mn) and nickel (Ni). To better understand...
Categories: Data;
Types: Citation;
Tags: Cook County,
Duluth,
Environmental Health,
Geochemistry,
Lake County,
It has been shown that Environmental Protection Agency (EPA) Method 3060A does not adequately extract Cr(VI) from solids containing chromium ore processing residue (COPR). We systematically modified parameters of EPA 3060A towards improving extraction efficiency of Cr(VI) from the National Institute of Standards and Technology (NIST) standard reference material (SRM) 2701, a standard COPR-contaminated soil from New Jersey, USA. A material similar to NIST 2701 prepared in the laboratory from contaminated soil referred to as 2B was also analyzed. Extraction parameters tested were particle size, glass or polytetrafluoroethylene (PTFE) extraction vessels, volume of extraction solution to mass of sample, and extraction...
Categories: Data;
Types: Citation;
Tags: CGGSC,
City of Denver,
Colorado,
Crustal Geophysics and Geochemistry Science Center,
EPA,
This dataset accompanies the publication, 'In situ LA-ICPMS U-Pb dating of cassiterite without a known-age matrix-matched reference material: Examples from worldwide tin deposits spanning the Proterozoic to Tertiary', published in Chemical Geology (https://doi.org/10.1016/j.chemgeo.2018.03.008), which reports a LA-ICPMS analytical procedure for dating cassiterite, a main ore mineral in tin deposits, with no need for an independently dated matrix-matched cassiterite standard.
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service,
Shapefile;
Tags: Bolivia,
Brazil,
China,
Geochemistry,
Geology, Geophysics, and Geochemistry Science Center,
Ar/Ar data are reported from minerals and rocks that were collected as part of a mineral resource investigation of the Tonopah, Divide, and Goldfield districts in Nevada. Data are reported from 92 samples and associated standards from eight separate neutron irradiations in the Denver USGS TRIGA reactor, including separated mineral grains and whole rocks. Data were collected by infrared laser heating of irradiated samples, either incremental heating or fusion, and analysis by multi-collector mass spectrometry. The reported data have been corrected for blanks, radioactive decay, and interfering nucleogenic reactions associated with sample irradiation.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 40Ar/39Ar,
Ar,
Divide district,
Geochemistry,
Goldfield,
This metadata record presents analytical results for laboratory microcosms conducted during 2016–18 as part of a study to develop a field test and numerical interpretation method to determine the effective diffusion coefficients and sorption coefficients of trichloroethene (TCE) and daughter products in the rock matrix of sedimentary rock, as well as biodegradation rate coefficients in the borehole. The biodegradation rate coefficients in the borehole are an important component of defining the back-diffusion of TCE from the matrix of sedimentary rock. Microcosm experiments were conducted with microbial community samples and groundwater collected from boreholes in the field test area to define anaerobic biodegradation...
On July 26, 2017, a solution containing approximately 200 kilograms of dissolved sodium bromide was added to the the flooded underground shaft of the Minnesota Mine, near Empire, Colorado. This addition was conducted as part of an effort to determine the degree to which the mine shaft is hydrologically connected to a series of downgradient seeps and springs. These seeps and springs discharge from the hillside and enter Lion Creek, an acidic, metal-rich stream that lies immediately to the west of the Minnesota Mine. A water quality sonde and pressure transducer deployed within the shaft recorded temperature, specific conductance, and stage before, during, and after the addition. The downgradient seeps and springs...
Categories: Data;
Tags: Empire, Colorado,
Environmental Health,
Geochemistry,
Hydrogeology,
Lion Creek,
Water analyses are reported for 66 samples collected from numerous thermal and non-thermal (rivers and streams) features in the southwestern areas of Yellowstone National Park (YNP) during 2009, 2017, and 2018. Water samples were collected from sources near Boundary Creek, Bechler River, Falls River, Mountain Ash Creek, Upper Snake River, Spirea Creek, and Lewis Lake. These water samples were collected and analyzed as part of research investigations on the chemistry of Yellowstone’s hydrothermal system and on the distribution of dissolved arsenic and mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen....
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Geochemistry,
Hydrology,
USGS Science Data Catalog (SDC),
Volcanology,
Water Quality,
Thirty-four ore, twenty-nine mine waste, seven host rock, two pegmatite, and one slag sample were collected from iron oxide-apatite (IOA) mines in the eastern Adirondack Highlands near Mineville and Ticonderoga, New York, from March 2016 to August 2018. The waste pile samples included twenty-five samples collected from rubble-sized mine waste piles and four samples from processed tailings piles. The ore from historic iron mines of the eastern Adirondack Highlands, New York, contain abundant quantities of rare earth element (REE)-bearing apatite crystals. These apatite crystals are especially enriched in Y, La, Ce, and Nd. In-ground ore, mine waste piles, and tailings piles could contain apatite...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Adirondack Mountains,
Energy Resources,
Geochemistry,
ICP-MS,
ICP-OES,
Note: This data release has been superseded by version 3.0, available here: https://doi.org/10.5066/P9Q2YP9K. The Hamilton Wetland Restoration Project (HWRP) is a joint venture between the US Army Corps of Engineers (USACE; San Francisco District) and the California State Coastal Conservancy. The site is located on the property of the former Hamilton Army Airfield in Novato, California, along the western edge of San Pablo Bay, which is part of northern San Francisco Bay. The initial stages of wetland restoration, which included dredged sediment reuse, took place during 2009–2011. From 2011 until April 2014, the site was maintained as partially flooded through a temporary one-way culvert that allowed bay water onto...
Categories: Data,
Data Release - Revised;
Tags: Geochemistry,
Novato,
San Francisco Bay,
San Pablo Bay,
USGS Science Data Catalog (SDC),
We computed mean groundwater ages and age distributions at eight wells by calibrating lumped parameter models (LPMs) to concentrations of tracers (3H, CFCs, SF6) in samples using the computer program TracerLPM (Jurgens and others, 2012). We also measured 14C but all samples contained ancient carbonate from the limestone bedrock, and we were unable to resolve the atmospherically-derived 14C sufficiently to use it as a tracer. Tritium was below the detection level in two of the eight well-water samples, indicating the water was recharged prior to about 1950. Groundwater from the other six wells could be fitted to LPMs that were either piston flow models (PFM), exponential – piston flow models (EPM), or binary mixing...
The dataset consists of geochemical and isotopic data from fine-grained sediments and glendonite crystals collected at Carter Creek on the North Slope of Alaska. Total Organic Carbon (TOC) values in the measured section were found to range between 0.5 and 3.5%, with a shift towards lower values in the uppermost 5 m of the section. Stable isotopes (13C) in organic matter were relatively stable throughout the section, ranging between -25.5 and -26, with a slight 0.3 per mil positive shift within this range approximately 57 m from the base of the section. Glendonites themselves were analyzed for δ13Ccarb and δ18Ocarb, with δ18O values relatively consistent between -0.22 and +1.28, and a much wider range of δ13C values...
The data in the csv and text files provided in this release are an update to the data tables originally published in USGS Open-File Report (OFR) 83-250 (https://doi.org/10.3133/cir892). Those data were published as paper tables and have until now only been available as pdf image documents that were not machine readable. USGS OFR 83-250 presented data for 2071 geothermal sites which are representative of 1168 low-temperature geothermal systems identified in 26 states. The low-temperature geothermal systems consist of 978 isolated hydrothermal-convection systems, 148 delineated-area hydrothermal-convection systems, and 42 delineated-area conduction-dominated systems. The basic data and estimates of reservoir conditions...
This data release contains selected results of whole-rock and glass analyses of lava samples collected during the 2018 eruption of Kilauea’s lower East Rift Zone (LERZ). Included are sampling-site information, eruptive vent/fissure, and sampling descriptions. During the 2018 LERZ eruption, the chemical analysis of lava samples was performed within hours of collection using an energy-dispersive X-ray fluorescence (ED-XRF) pressed-pellet methodology. The accuracy of this method was evaluated by analyzing a subset of samples using the more widely accepted wavelength dispersive X-ray fluorescence (WD-XRF) fused-bead methodology. WD-XRF analyses were performed both during and after the eruption at the Hamilton Analytical...
Categories: Data;
Tags: Geochemistry,
USGS Science Data Catalog (SDC),
Volcanology,
geochemistry,
volcanology
In situ geochemical data were obtained for pyrite crystals and native gold from two distinct vein sets in the Grass Valley gold district, California. Samples of the N-S veins were collected underground at the Empire Mine State Historic Park and samples of the E-W veins were collected from drill core provided by the Idaho-Maryland Mining Corporation in 2008. These geochemical data were analyzed to better understand paragenesis of quartz veins in orogenic gold deposits. Data includes electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) chemistry and LA-ICP-MS sulfur isotope values for pyrite crystals, and EPMA geochemistry of native gold grains found within...
This dataset accompanies planned publication 'Detrital record of the Late Oligocene – Early Miocene mafic volcanic arc in the Southern Patagonian Andes (~51°S) from single-clast geochronology and trace element geochemistry'. The Ar/Ar data is for samples that record the detrital sedimentary record of the basin. The geochronology provides time constraints for the sedimentation studied in the manuscript. Samples were collected from the Magallanes-Austral Basin, and collection was supervised by Julie Fosdick, who sent them to the USGS for Ar/Ar analysis.
In 1968, the Missouri Geological Survey (MGS) established the Operation Basement program to address three objectives: a) to obtain drill hole and underground mining data relative to the structure and composition of the buried Precambrian basement; b) to expand mapping in the Precambrian outcrop area and conduct research related to Precambrian geology and mineral resources; and c) to publish the results of the first two objectives in the Contribution to Precambrian Geology series (Kisvarsanyi, 1976). The database presented here represents the first of those objectives. It was originally compiled in close cooperation with exploration and mining companies operating in Missouri, who provided drillhole data, core and...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Adair County,
Andrew County,
Atchison County,
Audrain County,
Barry County,
This data release includes geochemical, x-ray diffraction mineralogical, and electron probe microanalysis (EPMA) data on rocks, soils, and sediments collected near the Orange Hill and Bond Creek porphyry copper deposits, Nabesna quadrangle, Alaska. Geochemical analyses were completed by a laboratory under contract with the U.S. Geological Survey (USGS). Electron microprobe and x-ray diffraction mineralogical analyses were completed by personnel of the Central Region Minerals Program in Denver, Colorado. The samples were collected and analyzed during 2014 to 2016, selected to help characterize the distribution and composition of mineralized and unmineralized geologic materials in this remote part of the eastern Alaska...
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Alaska,
Alaska Range,
Alder Gulch,
Bond Creek,
Chathenda Creek,
A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH and when coupled with long flow paths, results in the most alkaline conditions. Conversely, in areas where glacial sediments are thin and carbonate-poor, pH conditions remain acidic. At depths typical of drinking-water supplies, predicted pH > 7.5 – which is associated with arsenic mobilization – occurs more frequently...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted regression trees,
Calcite saturation index,
Connecticut,
Geochemistry,
Geochemistry,
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