Filters: Tags: carbon-14 analysis (X)
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This dataset consists of sample descriptions and radiocarbon age data from coastal environments on Montague Island, Alaska, analyzed at the National Ocean Sciences Accelerator Mass Spectrometry Facility.
Permafrost (perennially frozen) and active-layer (seasonally thawed) soils varying in soil carbon (C) and nitrogen (N) content and radiocarbon age were collected from three sites in interior Alaska to determine potential release of dissolved organic carbon (DOC), total dissolved N (TDN), dissolved organic nitrogen (DON), and dissolved inorganic nitrogen (DIN) upon thaw. Soil cores were cut into 15 cm thick sections, and deep active-layer (15-30 cm above the permafrost boundary) and shallow permafrost (15-30 cm below the permafrost boundary) sections were thawed and leached with deionized water. Soil leachates were analyzed for DOC, TDN, nitrate (NO3-), and ammonium (NH4+) concentrations, dissolved organic matter...
Categories: Data;
Tags: Alaska,
Ecology,
Soil Sciences,
USGS Science Data Catalog (SDC),
Water Quality,
This data release is part of a larger data release including data collected in the pursuit of identifying pre- and post-colonial riparian ecosystems found throughout Anne Arundel County, Maryland, USA. A single raster file is included, and represents a topological classification of the entire county according to a hydrologically conditioned Digital Elevation Model (DEM). These data were generated through the use of r.geomorphon, a GRASS GIS toolkit, to classify local terrain conditions into one of ten distinct landforms called geomorphons.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Anne Arundel,
Maryland,
Upper Chesapeake Bay,
carbon-14 analysis,
faunal and floral census (microscopic),
This portion of the data release presents radiocarbon age data from 66 samples collected from Anahola Valley (Kaua'i), Kahana Valley (O'ahu), and Pololu Valley (Hawai'i). Sample ages were determined by the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility. The data are provided in a comma-delimited spreadsheet (.csv).
Categories: Data;
Tags: Anahola Valley,
CMHRP,
Coastal and Marine Hazards and Resources Program,
Hawai'i,
Hawaiian Islands,
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.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: CMHRP,
Coastal and Marine Hazards and Resources Program,
Habitat,
Hooks Point,
Invertebrates,
This part of the release provides an updated georeferenced catalog of limestone boulders and cobbles pertaining to extreme waves on Anegada, a low Caribbean island perched south of the Puerto Rico Trench. Tabulated are 660 limestone clasts, along with clast dimensions and long-axis trend in many instances. Fewer than one-fifth of the clasts were reported previously in https://doi.org/10.1007/s11069-011-9725-8 and https://doi.org/10.1130/GES01356.1. Most were surveyed in 2017.
This data release provides geochemical, sedimentological, and geochronological data from interbedded fluvial and marsh deposits and radiocarbon dates of the section spanning the last 1500 years from the Pallett Creek paleoseismic site, California. The samples were collected to support paleoenvironmental reconstruction of the site and refine several previous investigations of paleoearthquakes along the San Andreas Fault (Sieh, 1978; Sieh, 1984; Sieh et al., 1989; Biasi and Weldon, 1994; Scharer et al., 2011). Geochemical and sedimentological data include grain size, magnetic susceptibility, dry bulk density, percent total organic matter, and percent total carbonate at contiguous 1 cm spacing and carbon (total C)...
Categories: Data,
Data Release - Revised;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Geomorphology,
Seismology,
Stratigraphy,
USGS Science Data Catalog (SDC),
carbon-14 analysis,
This part of the data release lists 18 localities where the shells of the tiger lucine Codakia orbicularis, a large marine bivalve, have been found on Anegada. Typically the shells were encountered a few tens of centimeters below ground in pits dug into sand. Most of the examples listed in the dataset were previously reported in https://doi.org/10.1130/GES01356.l -- field occurrences described p. 322, provenance interpreted p. 324, discordant radiocarbon ages discussed p. 324, and examples illustrated and mapped in Figure A9. The radiocarbon ages from lucines tabulated in this data set range across six radiocarbon centuries.
This release provides inventories of georeferenced evidence pertaining to extreme waves on Anegada, a low Caribbean island perched south of the Puerto Rico Trench: CORAL BOULDERS AND COBBLES -- Derived offshore, found inland. Boulder star coral Orbicella franksii (37 localities), brain coral Pseudodiploria strigosa (171), elkhorn coral Acropora palmata (36), mustard hill coral Porites astreoides (29). LIMESTONE BOULDERS AND COBBLES -- Derived and found onshore (633). MOLLUSCAN SHELLS -- Queen conch Aliger gigas, discarded by precolonial fishers (12 onshore heaps) and by modern fishers (40 offshore heaps); individual conch shells deposited inland by precolonial sea flood (59); tiger lucine Codakia orbicularis, also...
Results of radiocarbon dating of deep-sea (500 m to 700 m) black corals are presented. These corals were collected off the southeastern United States as part of the Southeastern United States Deep-Sea Corals (SEADESC) Initiative.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Atlantic Ocean,
CMHRP,
Coastal and Marine Hazards and Resources Program,
Ecology,
Geochemistry,
Sediment cores were collected in Great Dismal Swamp National Wildlife Refuge in November, 2017 to advance understanding of climate- and land-management driven changes in vegetation, hydrology, and fire regimes. Radiocarbon dates were obtained from samples in two cores (GDS-519-3-21-2017 and GDS-520-3-21-2017) to generate age models for the cores. Bulk sediment samples, charcoal, plant macrofossils, and pollen residue were selected at the USGS in Reston, Virginia and submitted to Beta Analytic, Inc. and the National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) laboratories for radiocarbon dating. Those laboratories provided both radiocarbon ages and stable carbon isotope (delta 13C) results, which can be...
This dataset contains isotope results of stable isotope (δ13C and δ15N) and radicoarbon (F14C) analyses of muscle tissue from fish collected in the nearshore Beaufort Sea, Alaska in summers 2017-2019.
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.
Categories: Data;
Tags: Atlantic Ocean,
CMHRP,
Chemical analysis,
Coastal and Marine Hazards and Resources Program,
Geochemistry,
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).
This dataset holds data associated with the stratigraphic descriptions and grain size analyses and the radiocarbon age dating for the journal article "Stratigraphy and eruption history of maars in the Clear Lake Volcanic Field, California"
Categories: Data;
Tags: California,
Lake,
Stratigraphy,
USGS Science Data Catalog (SDC),
Volcanology,
This data release includes geochronological data for the Airport East trench site (40.795359°, -111.950438°) on the Taylorsville fault of the West Valley fault zone (WVFZ). The WVFZ comprises intrabasin faults in the hanging wall of the Wasatch fault zone in the northern part of Salt Lake Valley, Utah. Samples for radiocarbon and luminescence dating were collected from two paleoseismic trenches in August–September 2015. Laboratory data include four optically stimulated luminescence ages and 14 radiocarbon ages for charcoal extracted from bulk sediment samples. This database has been approved for release by the U.S. Geological Survey (USGS). Although this database has been subjected to rigorous review and is substantially...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Geomorphology,
Salt Lake City,
Salt Lake Valley,
Sedimentology,
Seismology,
Charcoal counts and radiocarbon dates from four sediment cores collected in Great Dismal Swamp in 2017 and 2018 were incorporated into a synthesis of charcoal records from northern hemisphere peatlands (Sims et al., in review). Macroscopic charcoal was counted in three size classes: 125-250 micrometers, and 250-500 micrometers, and >500 micrometers. Uncalibrated radiocarbon dates were obtained and provided for use in development of age models for analyses by Sims et al., in review).
This database contains a comprehensive inventory of geologic (coral, coral reef, limestone, and sediment) cores and samples collected, analyzed, published, and/or archived by, or in collaboration with, the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC). The SPCMSC Geologic Core and Sample Database includes geologic cores and samples collected beginning in the 1970s to present day, from study sites across the world. This database can be accessed through the CoreViewer 3.0 ArcOnline web mapping application, linked below. A copy of the data can also be downloaded from the web mapping application and the metadata is accessible through a link in the header of the application, as...
Categories: Collection,
Data;
Tags: Alabama,
Atlantic Ocean,
Bahamas,
Belize,
Biological Collection,
This dataset consists of sample details and radiocarbon age data of tree-ring samples collected near Girdwood, Alaska, and analyzed at the National Ocean Sciences Accelerator Mass Spectrometry Facility.
This part of the data release provides an updated georeferenced list of radiocarbon ages pertaining to evidence for a catastrophic precolonial sea flood on Anegada, a low Caribbean island perched south of the Puerto Rico Trench. The list contains 64 ages measured on carbonate materials and 3 ages measured on plant fragments. Among the total of 67 ages, 43 are among the 47 ages previously tabulated on page 318 of https://doi.org/10.1130/GES01356.l. The 67 ages exclude those from previous work on deposits attributable to the 1755 Lisbon tsunami (https://doi.org/10.1007/s11069-010-9622-6). Among the 67 ages listed, the 24 ages previously unreported were measured mainly on samples collected in 2017. The main material...
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