Geochemistry

the study of the chemical composition and genesis of earth materials.

24 results listed alphabetically [list by similarity]
Biomarker analysis of cold seeps along the United States Atlantic Margin

Results of lipid biomarker concentration and compound specific isotopes analyzed from authigenic carbonates and surrounding sediment collected from Baltimore and Norfolk seep fields along the United States Atlantic Margin are presented in csv format. Samples were collected by the U.S. Geological Survey and Duke University between 2012 and 2015 using remotely operated vehicles (ROVs). Geochemical analysis was performed using gas chromatography (GC) and GC-combustion isotope ratio mass spectrometry (GC-C-IRMS ...

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Comparison of methane concentration and stable carbon isotope data for natural samples analyzed by discrete sample introduction module - cavity ring down spectroscopy (DSIM-CRDS) and traditional methods

A discrete sample introduction module (DSIM) was developed and interfaced to a cavity ring-down spectrometer to enable measurements of methane and CO2 concentrations and 13C values with a commercially available cavity ring-down spectrometer (CRDS). The DSIM-CRDS system permits the analysis of limited volume (5 - 100-ml) samples ranging six orders-of-magnitude from 100% analyte to the lower limit of instrument detection (2 ppm). We demonstrate system performance for methane by comparing concentrations and ...

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Coral growth parameters, Kahekili, west Maui

Surface runoff and submarine groundwater discharge in particular are known vectors to the coastal ocean of elevated nutrients and contaminants leading to eutrophication, algal overgrowth, and coral disease. Freshwater discharging directly from submarine groundwater vents off of Kahekili Beach Park, Kaanapali, in West Maui contains elevated nutrient concentrations and lower pH values. Coral cores were collected in July 2013 from the shallow reef at Kahekili in Kaanapali, West Maui, Hawaii from ...

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CTD (Conductivity Temperature Depth) data collected October-November 2019 offshore of California and Oregon

CTD (Conductivity Temperature Depth) data were collected October-November 2019 offshore of California and Oregon as part of the ongoing EXPRESS: Expanding Pacific Research and Exploration of Submerged Systems project. The data were collected using an SBE 49 FastCAT V 1.2a CTD profiler attached to the “Yogi” ROV launched from the National Oceanic and Atmospheric Administration’s (NOAA’s) R/V Reuben Lasker (NOAA cruise R-19-05).

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CTD profile measurements collected off California and Oregon during NOAA cruise RL-19-05 (USGS field activity 2019-672-FA) from October to November 2019

CTD (Conductivity Temperature Depth) data were collected offshore of California and Oregon from October to November 2019 during NOAA cruise RL-19-05 (USGS field activity 2019-672-FA). This data release supersedes version 1.0, published in August 2020 at https://doi.org/10.5066/P9ZS1JX8. Versioning details are documented in the accompanying VersionHistory_P9JKYWQU.txt file.

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CTD profile measurements collected off California and Oregon during NOAA cruise SH-18-12 (USGS field activity 2018-663-FA) from October to November 2018

CTD (Conductivity Temperature Depth) data were collected offshore of California and Oregon from October to November 2018 during NOAA cruise SH-18-12 on the R/V Bell M. Shimada (USGS field activity 2018-663-FA). This data release supersedes version 2.0, published in September 2021 at https://doi.org/10.5066/P99DIQZ5. Versioning details are documented in the accompanying VersionHistory_P99MJ096.txt file.

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Geochemical analysis of authigenic carbonates and chemosynthetic mussels at Atlantic Margin seeps (ver. 2.0, March 2019)

Isotopic analyses of authigenic carbonates and methanotrophic deep-sea mussels, Bathymodiolus sp., was performed on samples collected from seep fields in the Baltimore and Norfolk Canyons on the north Atlantic margin. Samples were collected using remotely operated underwater vehicles (ROVs) during three different research cruises in 2012, 2013, and 2015. Analyses were performed by several different laboratories, and the results are presented in spreadsheet format.

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Geochemical analysis of seeps along the Queen Charlotte Fault

Geochemical analyses of authigenic carbonates, bivalves, and pore fluids were performed on samples collected from seep fields along the Queen Charlotte Fault, a right lateral transform boundary that separates the Pacific and North American tectonic plates. Samples were collected using grab samplers and piston cores, and were collected during three different research cruises in 2011, 2015, and 2017.

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Geochemical and isotopic compositions of stream sediment, parent rock, and nearshore sediment from southwest Puerto Rico, April 2017-June 2018

Geochemical and isotopic compositions were determined in stream sediment and parent rocks collected in April 2017 and June 2017 and in nearshore sediment collected bimonthly in sediment traps from May 2017 to June 2018 in the coastal zone and 12 drainages of southwest Puerto Rico: Rio Loco, Yauco, Guayanilla, Macana, Tallaboa, Matilde, Portugues, Bucana, Inabon, Jacaquas, Descalabrado, and Coamo. Geochemical compositional data include: a) total contents of major, minor, trace, and rare earth elements in the ...

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Geochemistry of fine-grained sediment in Bellingham Bay, Nooksack River, and small creeks from June 2017 to September 2019

Elemental compositions are reported for the fine fraction of surface sediments from Bellingham Bay (June 2017 and March 2019) and in the fine fraction of streambank sediment from the Nooksack River (September 2017, March 2019, September 2019), Squalicum Creek (March and September 2019), Whatcom Creek (March and September 2019), and Padden Creek (March and September 2019). Major oxide percentages are reported in Nooksack River fine sediment collected in September 2017. Ancillary data for sediment collected ...

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Geochemistry of sediment and organic matter in drainages burned by the Altas and Nuns wildfires in October 2017 and of nearshore seabed sediment in north San Francisco Bay from March to April 2018

Fine-grained sediment was collected from the banks of Napa River, Sonoma Creek, and tributaries in March 2018 and from shallow nearshore areas of the northern reach of San Francisco Bay in April 2018. Bulk sediment was dated using activities of short-lived cosmogenic radionuclides (beryllium-7, cesium-137, and lead-210). Contents of potentially toxic metals and source-rock-indicative elements, including rare earth elements, were quantified in the fine fraction of sediment (particles less than 0.063 mm ...

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Geophysical properties, geochronologic, and geochemical data of sediment cores collected from San Pablo Bay, California, October 17-20, 2016

Geophysical properties (P-wave velocity, gamma ray density, and magnetic susceptibility), geochronologic (radiocarbon, excess Lead-210, and Cesium-137), and geochemical data (organic carbon content and 60 element contents) are reported for select vibracores collected aboard the S/V Retriever October 17-20, 2016, in San Pablo Bay, California. Geophysical properties were measured with a Geotek Multi-Sensor Core Logger (MSCL). Radiocarbon was measured by accelerator mass spectrometry (AMS). Excess Lead-210 and ...

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Inorganic compositional data for fine-grained Puget Sound sediment along the Burlington Northern Santa Fe rail line, September 2015

Nearshore surface sediment was collected with a petit ponar grab sampler between April 22 and September 17, 2015, at five sites in Puget Sound, Washington. Four sites were adjacent to the Burlington Northern Santa Fe rail line in urban and non-urban areas, and one site was in an urban area that was not adjacent to the rail line. Total and near-total major, minor, trace, and rare earth element contents of the <0.063 mm sediment fraction were determined by inductively coupled plasma atomic emission ...

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Microbial Ecology of the Floridan Aquifer near Okeechobee, FL

This metadata record describes the microbial uptake of nutrients by native planktonic and biofilm-associated bacteria within the Upper Floridan Aquifer (approximately 1,000 feet below land surface) in the Okeechobee, Florida area. Groundwater samples were collected between 2018 and 2019 from a South Florida Water Management District (SFWMD) monitoring well installed at the Kissimmee River Aquifer Storage and Recovery (ASR) facility, which is located at the discharge point of the Kissimmee River into Lake ...

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Mineralogy, rare earth elements, and strontium isotopic composition of phosphorites and phosphatized rocks from the Rio Grande Rise, south Atlantic Ocean

Phosphorites and phosphatized rocks from the summit of the Rio Grande Rise (RGR) in the south Atlantic Ocean were collected via dredge during the oceanographic research cruise RGR1 to the western RGR. The location (latitude, longitude, depth), mineralogy, concentrations of phosphorus and rare earth elements, and 87Sr/86Sr ratios of phosphorites and phosphatized FeMn crusts, ironstones, and carbonates from 10 dredge sites are presented here. These data were used to determine the presence of carbonate ...

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Olowalu chronology and geochemistry time-series, West Maui

Chronology and time-series geochemistry data of a coral core collected from Olowalu, West Maui, Hawaii. The chronology is based on density banding, radiocarbon bomb-curve, and uranium thorium dating techniques. The geochemistry time-series data contains major and minor elements over the length of the coral life span, as measured from laser ablation inductively coupled mass spectrometry (LA-ICP-MS).

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Polycyclic aromatic hydrocarbons (PAHs) in the San Lorenzo River, Santa Cruz, California, USA, from 2015 to 2016

Polycyclic aromatic hydrocarbons (PAHs) are reported for water samples collected from the San Lorenzo River water during the rainy seasons from 2015 to 2016. Samples were collected during 2-, 5- and close to 10 year flood events.

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Results from isotope analysis of authigenic carbonates collected offshore the U.S. Mid- and South Atlantic

Geochemical analysis of carbonate rock samples collected from seep fields on the RB1903 and AT41 research expeditions in the U.S. Mid- and South Atlantic. Samples were collected as a fingerprint to past hydrocarbon seep activity, fluid source, and depositional environment.

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Seawater carbonate chemistry, Kahekili, west Maui

Time-series of seawater carbonate chemistry variables, including salinity, dissolved inorganic nutrients, pH, total alkalinity, and dissolved inorganic carbon from sites along Kahekili Beach Park, west Maui near submarine groundwater seeps and living coral reefs. Samples for seawater were collected by pumping bottom water from the seafloor using a peristaltic pump and collecting discrete water samples every 4-hrs over a 6-day period.

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Sediment trap and water column chemistry, Baltimore Canyon, U.S. Mid-Atlantic Bight

Time-series of sediment chemistry, including organic biomarker composition and bulk inorganic geochemical analytes, from samples collected over a one-year period in a sediment trap. The sediment traps were deployed at a depth between 603 m to 1318 m, and they were programmed to rotate a 250 mL sample bottle at 30 d intervals, delivering 12 samples during the 1-year deployment between August 2012 and June 2013. In addition, dissolved water column nutrient concentrations and water column trace element ...

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Sorbed-water (H2O-) corrected chemistry for ferromanganese crust samples from the western equatorial Pacific Ocean

Ferromanganese crust samples were collected via dredge during four oceanographic research cruises to the western equatorial Pacific Ocean. The location (latitude, longitude, depth) and concentrations of 27 major and trace elements in the most recent growth layers of ferromanganese crusts from 57 dredge sites are presented here, as well as select seawater chemistry at each location. These data were used in statistical analyses to determine how oceanographic conditions affect the chemical composition of ...

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Suspended sediment concentration (SSC) in the San Lorenzo River, Santa Cruz, California, USA, from 2008 to 2019

Suspended-sediment concentrations are reported in mg/L for water samples collected from the San Lorenzo River during the rainy seasons from 2008 to 2019. Samples were collected during 2-, 5- and 10-year flood events.

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Water-column environmental variables and accompanying discrete CTD measurements collected off California and Oregon during NOAA cruise SH-18-12 (USGS field activity 2018-663-FA) from October to November 2018 (ver. 3.0, July 2022)

Various water column variables, including salinity, dissolved inorganic nutrients, pH, total alkalinity, dissolved inorganic carbon, radio-carbon isotopes were measured in samples collected using a Niskin-bottle rosette at selected depths from sites offshore of California and Oregon from October to November 2018 during NOAA cruise SH-18-12 on the R/V Bell M. Shimada (USGS field activity 2018-663-FA). CTD (Conductivity Temperature Depth) data were also collected at each depth that a Niskin-bottle sample was ...

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Water-column environmental variables and accompanying discrete CTD measurements collected off California and Oregon during NOAA Ship Lasker R-19-05 (USGS field activity 2019-672-FA) from October to November 2019 (ver. 2.0, July 2022)

Various water column variables, including salinity, dissolved inorganic nutrients, pH, total alkalinity, dissolved inorganic carbon, radio-carbon isotopes were measured in samples collected using a Niskin-bottle rosette at selected depths from sites offshore of California and Oregon from October to November 2019 during NOAA Ship Lasker R-19-05 (USGS field activity 2019-672-FA). CTD (Conductivity Temperature Depth) data were also collected at each depth that a Niskin-bottle sample was collected and are ...

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