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Natural cave passages penetrating a coastal aquifer in the Yucatan Peninsula (Mexico) were accessed to test the hypothesis that chemoclines associated with salinity gradients (haloclines) within the flooded cave networks of the karst subterranean estuary are sites of methane oxidation. Two field trips were carried out to the fully-submerged cave system located 6.6 km inland from the coastline in January 2015 and January 2016. Vertical chemical profiles across the water column haloclines were obtained using the OctoPiPi (OPP), a high-resolution water sampler built by the U.S. Geological Survey (USGS). The sampling efforts resulted in cm-scale profiles of major ions (e.g., chloride and sulfate), as well as concentrations...
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The accretion history of fringing salt marshes located on the south shore of Cape Cod is reconstructed from sediment cores collected in low and high marsh vegetation zones. These marshes are micro-tidal, with a mean tidal range of 0.442 m. Their location within protected embayments and the absence of large rivers results in minimal sediment supply and a dominance of organic matter contributions to sediment peat. Age models based on 210-lead and 137-cesium are constructed to evaluate how vertical accretion and carbon burial rates have changed over the past century. The continuous rate of supply age model was used to age date 11 cores (10 low marsh and 1 high marsh) across four salt marshes. Both vertical accretion...
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These datasets are from an incubation experiment with a combination of two minerals (feldspar or amorphous aluminum hydroxide), one living species of bacteria (Escherichia coli), and one added form of C (Arthrobacter crystallopoietes necromass). We characterized the sorptive properties of the minerals with batch sorption experiments using four low molecular weight C substrates (glucose, oxalic acid, glutamic acid, p-hydroxybenzoic acid): this data is provided in the SterileSorptionData file. We then conducted a 3-wk long incubation in serum vials or imaging chambers. In both incubations, feldspar (200 mg) or amorphous aluminum hydroxide (100 mg) was given 1 of 4 different treatments: (1) a water control with autoclaved...
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This dataset contains stable isotope (δ13C) and radioisotope (Δ14C) compositions of dissolved inorganic carbon, dissolved organic carbon, particulate organic carbon, and bed material organic carbon samples collected from rivers in the Upper Mississippi River Basin between October 2014 and February 2016. Rivers were sampled at USGS gaging stations: Minnesota River at Fort Snelling State Park, MN (gage #05330920), Mississippi River at Hwy 610 in Brooklyn Park, MN (gage #05288500), St. Croix River at Prescott, WI (gage #05344490), Mississippi River at Prescott, WI (gage #05344500), and Chippewa River at Durand, WI (gage #05369500). One site was also sampled at a location that is not co-located with a gaging station:...
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These data consist of sulfur and carbon isotope compositions, concentrations of selected elements, and concentrations of pyrite sulfur and organic carbon in mudstone samples collected from five cores drilled in the Howards Pass district, Yukon-Northwest Territories, Canada. The cores were drilled between 2006 and 2014, site visits and core sampling took place between 2009 and 2016, and laboratory work was conducted between 2011 and 2017. The data were obtained as part of a research project described in the following publication: Johnson, Craig A., Slack John F., Dumoulin, Julie A., Kelley, Karen D., and Falck, Hendrick, 2018, Sulfur isotopes of host strata for Howards Pass (Yukon-Northwest Territories) Zn-Pb deposits...
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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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Radiocarbon dating of silicified wood was performed at the U.S. Geological Survey’s Radiocarbon Laboratory in Denver, Colorado. All samples were chemically treated using the standard acid-base-acid (ABA) procedure before being combusted online in the presence of excess high-purity oxygen. Water and other contaminant gases were removed using cryogenic separation techniques, and the resulting purified CO2 gas was measured manometrically and converted to graphite using an iron catalyst and hydrogen reduction (Vogel et al., 1984). Graphite targets were then submitted for accelerator mass spectrometry 14C analysis at the National Ocean Sciences Accelerator Mass Spectrometry facility in Woods Hole, Massachusetts. All...
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These datasets are from an incubation experiment with a combination of two minerals (feldspar or amorphous aluminum hydroxide), one living species of bacteria (Escherichia coli), and one added form of C (Arthrobacter crystallopoietes necromass). We characterized the sorptive properties of the minerals with batch sorption experiments using four low molecular weight C substrates (glucose, oxalic acid, glutamic acid, p-hydroxybenzoic acid): this data is provided in the SterileSorptionData file. We then conducted a 3-wk long incubation in serum vials or imaging chambers. In both incubations, feldspar (200 mg) or amorphous aluminum hydroxide (100 mg) was given 1 of 4 different treatments: (1) a water control with autoclaved...
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Natural cave passages penetrating a coastal aquifer in the Yucatan Peninsula (Mexico) were accessed to investigate how regional meteorology and hydrology control methane dynamics in karst subterranean estuaries. Three field trips were carried out in January 2015, June 2015, and January 2016 to obtain year-long high-resolution temporal records of water chemistry and environmental parameters below and above the surface at a site (Cenote Bang) within the Ox Bel Ha cave network. These efforts resulted in chemical records of dissolved methane concentrations and its stable carbon isotopic content and major ion concentrations (i.e., chloride and sulfate) in approximately 2.5-day resolution from January 2015 to January...
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This dataset presents the results of analysis of aquatic biota tissue samples, collected over multiple sampling events from in from 2007 to 2014 at three sites (Las Vegas Bay, Overton Arm, and Boulder Basin) in Lake Mead National Recreational Area. The tissue samples were analyzed for concentrations of Carbon 13 and Nitrogen 15 isotopes by the University of California, Davis in Davis, California. Data are presented in 1 spreadsheet worksheet that is organized by year, location, and taxa. General trophic level (Vander Zanden and Rasmussen, 1999) and calculations of benthic reliance (Umek and others, 2010) also are included. Combined data from sampling events in 2007 and 2008 previously were published in Umek and...
Categories: Data; Tags: Boulder Basin, Colorado River, Lake Mead, Lake Mead National Recreational Area, Las Vegas, All tags...
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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 the site. On April 25th, 2014, the outboard levee towards the north-eastern corner of the site was breached...
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This dataset presents the results of passive water sampling conducted at 2 sites in 2013 and 3 sites in 2014 in Lake Mead National Recreational Area. Polar Organic Chemical Integrative Samplers (POCIS) and Semipermeable Membrane Devices (SPMDs) were deployed in Las Vegas Bay and Overton Arm in 2013 and Las Vegas Bay, Boulder Basin, and Overton Arm in 2014. The samplers were analyzed for concentrations of polychlorinated biphenyls (PCBs), organochlorines (DDT-type compounds and their degradates), polybrominated biphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), waste indicators (WW), and yeast estrogen screen (YES) by the U.S. Geological Survey (USGS) at the Columbia Environmental Research Center (CERC)...
Categories: Data; Tags: Boulder Basin, Colorado River, Lake Mead, Lake Mead National Recreational Area, Las Vegas, All tags...
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Old Faithful Geyser in the Upper Geyser Basin of Yellowstone National Park is one of the best studied geysers in the world. Under research permit YELL-SCI-8030, samples from 13 silicified tree remnants were collected adjacent to the Old Faithful Geyser cone in April and November 2019. The silicified wood samples were dated using the radiocarbon (14C) method and were analyzed by scanning electron microscope (SEM) to determine the extent of wood silicification. This study was conducted in order to provide new information on the geyser’s past decadal to centennial eruptive activity. Understanding Old Faithful’s past could provide a baseline for understanding future changes in its eruption intervals.
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Silicified wood samples were vacuum impregnated with epoxy, sectioned, and sputter coated with 10 nm Au/Pd at the U.S. Geological Survey, Menlo Park, CA. Samples were imaged in a Tescan VEGA3 Scanning Electron Microscope (SEM) equipped with an Oxford 150 mm2 X-MaxN large area energy dispersive spectrometer at the U.S. Geological Survey, Menlo Park, CA. Backscatter (BSE) images were collected with an accelerating voltage (HV) of 30 kV and a working distance (WD) of ~15 mm. Magnification is indicated on individual images. The data files for Scanning Electron Microsocopy (SEM) contain representative SEM-BSE images of samples OFL101 and OFL103-2. This research was conducted under Yellowstone Research Permit YELL-SCI-8030.
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This dataset presents the results of analysis of aquatic biota tissue samples, collected at 2 sites (Las Vegas Bay and Overton Arm) in 2013 and 2 sites (Las Vegas Bay, Boulder Basin, and Overton Arm) in 2014 in Lake Mead National Recreational Area. The tissue samples were analyzed for concentrations of more than 250 compounds and congeners of polychlorinated biphenyls (PCBs), organochlorine pesticides (DDT and its degradates), wastewater chemicals, and polybrominated diphenyl ethers (PBDEs) by the U.S. Geological Survey (USGS) at the Columbia Environmental Research Center (CERC) in Columbia, Missouri. Analysis methods include low-resolution, high-resolution, and full spectrum mass spectrometry and high-resolution...
Categories: Data; Tags: Boulder Basin, Colorado River, Lake Mead, Lake Mead National Recreational Area, Las Vegas, All tags...


    map background search result map search result map Isotopic and chemical composition (δ13C, Δ14C, δ15N, C:N, SUVA254nm, % HPOA) of aquatic carbon and field conditions (water temperature, pH, discharge) in the Upper Mississippi River Basin, October 2014 – February 2016 Data and calculations to support the study of the sea-air flux of methane and carbon dioxide on the West Spitsbergen margin in June 2014 Data for Analysis of Endocrine Disrupting Compounds in Lake Mead National Recreation Area near Las Vegas, Nevada Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Isotope and chemical data for: Sulfur isotopes of host strata for Howards Pass (Yukon-Northwest Territories) Zn-Pb deposits implicate anaerobic oxidation of methane not basin stagnation Temporal hydrologic and chemical records from the Ox Bel Ha cave network within the coastal aquifer of the Yucatan Peninsula, from January 2015 to January 2016 Stable Isotopes in Biota in Lake Mead National Recreation Area near Las Vegas, Nevada Synthetic Organic Compounds in Biota in Lake Mead National Recreation Area near Las Vegas, Nevada Synthetic Organic Compounds in Water in Lake Mead National Recreation Area near Las Vegas, Nevada Vertical chemical profiles collected across haloclines in the water column of the Ox Bel Ha cave network within the coastal aquifer of the Yucatan Peninsula in January 2015 and January 2016 Silicified wood from around Old Faithful Geyser, Yellowstone National Park Radiocarbon Dating Mercury speciation and other constituent data for surface water and bed sediment associated with the Hamilton Airfield Wetland Restoration, Novato, California. USA Scanning Electron Microscopy (SEM) Radiocarbon Dating Scanning Electron Microscopy (SEM) Silicified wood from around Old Faithful Geyser, Yellowstone National Park Mercury speciation and other constituent data for surface water and bed sediment associated with the Hamilton Airfield Wetland Restoration, Novato, California. USA Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Vertical chemical profiles collected across haloclines in the water column of the Ox Bel Ha cave network within the coastal aquifer of the Yucatan Peninsula in January 2015 and January 2016 Temporal hydrologic and chemical records from the Ox Bel Ha cave network within the coastal aquifer of the Yucatan Peninsula, from January 2015 to January 2016 Data for Analysis of Endocrine Disrupting Compounds in Lake Mead National Recreation Area near Las Vegas, Nevada Stable Isotopes in Biota in Lake Mead National Recreation Area near Las Vegas, Nevada Synthetic Organic Compounds in Biota in Lake Mead National Recreation Area near Las Vegas, Nevada Synthetic Organic Compounds in Water in Lake Mead National Recreation Area near Las Vegas, Nevada Isotopic and chemical composition (δ13C, Δ14C, δ15N, C:N, SUVA254nm, % HPOA) of aquatic carbon and field conditions (water temperature, pH, discharge) in the Upper Mississippi River Basin, October 2014 – February 2016 Isotope and chemical data for: Sulfur isotopes of host strata for Howards Pass (Yukon-Northwest Territories) Zn-Pb deposits implicate anaerobic oxidation of methane not basin stagnation Data and calculations to support the study of the sea-air flux of methane and carbon dioxide on the West Spitsbergen margin in June 2014