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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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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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The dataset includes multiple file types (CSV, ArcGIS shapefiles, and images), data relates to the elemental analysis of fish otoliths. Otoliths examined in this study were from randomly-sampled individual Tidewater Goby (Eucyclogobius newberryi) and Prickly Sculpin (Cottus asper) from the adult population of Rodeo Lagoon and Rodeo Creek, Marin County, California. The fish were collected in April and August 2016.
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Geochemical analysis of authigenic carbonates from the Cascadia Subduction Zone. Powdered carbonate samples for stable carbon (delta-C-13) and oxygen (delta-O-18) isotopes and carbonate phase were analyzed as a proxy for potential fluid sources, and to better understand how process, such as mixing, and oxidation, can alter the initial fluid isotopic composition and the archived fluid-source signature in the authigenic carbonates.
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The urbanized area of downtown Menlo Park is subject to persistent flooding and sediment deposition by San Francisquito Creek in South San Francisco Bay. To mitigate these events, a suite of cores was collected in 2002 at the mouth of the creek to determine sediment depositional rates on the delta. One of those cores (721-1) was selected for microbiological (pollen, diatoms, and foraminifera) and geochemical analyses to reconstruct a depositional record over the past two millennia. This data release provides radiocarbon dates, census counts of benthic foraminifera, diatoms, and palynomorphs, and the measurement of anthropogenic metals and other elements in sediments from this core.
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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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This portion of the data release presents water column dissolved nutrient concentration data and water quality parameters from samples collected in the Elwha River estuary, Washington, in 2006, 2007, 2013, and 2014 (USGS Field Activities L-15-13-PS, L-24-13-PS, T-R5-13-PS, T-R6-13-PS, T-RA-14-PS, 2014-614-FA, 2014-628-FA, 2014-633-FA, 2014-666-FA). Water column samples were collected by hand in acid-washed opaque bottles from multiple locations. Water quality was measured using a handheld Hydolab Data Sonde 4a. The locations of water sample collections were determined with a hand-held global positioning system (GPS). The water samples were filtered through GF/F filters immediately after collection. The filtrate...
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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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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 13C results obtained by the DSIM and traditional methods for a variety of sample types, including low concentration (nanomolar) seawater and high concentration (> 90%) natural gas. The expansive concentration range...
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These data are a part of the effort to map geologic substrates of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts. The overall goal is to develop high-resolution (1:25,000) interpretive maps, based on multibeam sonar data and seabed sampling, showing surficial geology and seabed sediment dynamics. The work was conducted in collaboration with the Stellwagen Bank National Marine Sanctuary, and the data collected will aid research on the ecology of fish and invertebrate species that inhabit the region. The Sanctuary's research vessel, R/V Auk, visited a total of 233 locations on Stellwagen Bank during six separate surveys from May 2016 to April 2019. During these surveys a customized...
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A critical question for assessing global greenhouse gas budgets is how much of the methane that escapes from seafloor cold seep sites to the overlying water column eventually crosses the sea-air interface and reaches the atmosphere. The issue is particularly important in Arctic Ocean waters since rapid warming there increases the likelihood that gas hydrate--an ice-like form of methane and water stable at particular pressure and temperature conditions within marine sediments--will break down and release its methane to the overlying ocean. Some researchers have even proposed the possibility of an Arctic methane catastrophe characterized by wholesale breakdown of gas hydrates in marine sediments and release of the...
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Geochemical analysis (including age-corrected radiocarbon stable isotopes, and elemental composition) and growth parameters (including calcification rate, density, and extension information) were measured from a coral core collected from a reef off the southern side of Tutuila, American Samoa. The core was collected near Matautuloa Point on 8 April 2012 in collaboration with the Ecosystem Sciences Division, Pacific Islands Fisheries Science Center, National Oceanic and Atmospheric Administration (NOAA), Honolulu, HI.
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First release: 2016 Revised: 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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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 presented along with the water sample data. 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...
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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 particulate concentrations were collected in Baltimore Canyon on the U.S. Mid-Atlantic Bight (MAB).