Filters: partyWithName: U.S. Geological Survey (X) > partyWithName: U.S. Geological Survey - ScienceBase (X) > partyWithName: Geosciences and Environmental Change Science Center (X) > Categories: Data (X)11 results (87ms)
Digital subsurface data of Mesozoic rocks in the Upper Colorado River Basin in Wyoming, Utah, Colorado, Arizona, and New Mexico from USGS Regional Aquifer System Analysis
The Upper Colorado River Basin has a drainage area of about 113,500 square miles in western Colorado, eastern Utah, southwestern Wyoming, northeastern Arizona, and northwestern New Mexico. In the 1980’s and 1990’s, the Upper Colorado River Basin was a study area under of the U.S. Geological Survey's Regional Aquifer-System Analysis (RASA) program (Sun and Johnston, 1994; Sun and Weeks, 1991). The objectives of the RASA program for the Upper Colorado River Basin were to provide regional assessments of major aquifer systems by providing quantitative assessments of the occurrence, movement, and availability of water stored in rock formations that underlie the basin/watershed. These assessments included: (1) the classification...
DATA RELEASE Part 2: Optical luminescence dating of Bradley Lake, Oregon, tsunami deposits, analytical data for: A maximum rupture model for the central and southern Cascadia subduction zone—reassessing ages for coastal evidence of megathrust earthquakes and tsunamis
The following report summarizes the dating results from Bradley Lake, Oregon. Within this report, we detail the methodology used by the USGS Luminescence Geochronology Laboratory to obtain ages including sample preparation methods, luminescence measurement, equivalent dose determination, and datingrelated calculations. We recommend that this report be included as the supplementary material for any publication(s) that use the ages within this report. This version supersedes all previous age estimates and reports.
U-series isotope data used to date a 130,000-year-old archaeological site in southern California, U.S.A.
This dataset includes tables with physical information and isotopic data that are used to calculate uranium-series ages (230Th/U method) and initial 234U/238U activity ratios on a suite of mastodon bones from the Cerutti Mastodon site near San Diego, CA area.
Data release for Isotopic constraints on middle Pleistocene cave evolution, paleohydrologic flow, and environmental conditions from Fitton Cave speleothems, Buffalo National River, Arkansas (KIG'17)
This dataset accompanies publication 'Isotopic constraints on middle Pleistocene cave evolution, paleohydrologic flow, and environmental conditions from Fitton Cave speleothems, Buffalo National River, Arkansas', published as a contribution to USGS Scientific Investigations Report 2017-5023 associated with the 2017 USGS Karst Interest Group meeting in San Antonio, TX.
Data release of OSL, 14C, and U-series age data supporting geologic mapping along the South Platte River corridor in northeastern Colorado
In conjunction with geologic mapping of four 7.5′ quadrangles along the South Platte River corridor in northeastern Colorado (Masters, Orchard, Weldona, and Fort Morgan), geochronology samples were collected and analyzed using optically stimulated luminescence (OSL), radiocarbon (14C), or U-series methods to provide age control for mapping units. This section of river corridor is largely covered by surficial deposits that formed from alluvial, eolian, and hillslope processes operating in concert with environmental changes from the Pleistocene to the present. The South Platte River originates high in the Colorado Rocky Mountains and recurrent glaciation of basin headwaters has affected river discharge and sediment...
Data release for Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: Process, timing, and downstream implications
This dataset includes tables of 3He-isotopic data used to calculate surface exposure ages for samples of basalt, and U- and Th-isotopic data used to calculate uranium-series age estimates (230Th/U method) and initial 234U/238U activity ratios for samples of pedogenic carbonate formed in soils on alluvial fans in the San Luis Valley, Colorado, USA. These data are included in the publication: Ruleman, C.A., Hudson, A.M., Thompson, R.A., Miggins, D.P., Paces, J.B., Goehring, B.M., 2019, Middle Pleistocene formation of the Rio Grande Gorge, San Luis Valley, south-central Colorado and north-central New Mexico, USA: process, timing, and downstream implications. Quaternary Science Reviews 223, https://doi.org/10.1016/j.quascirev.2019.07.028.
Hourly carbon dioxide (CO2) measurements from four locations of snowpack profiles with vertical spacing of 20 cm over seven winters (2010-2016) at the Glacier Lakes Ecosystem Experiments Site (GLEES) in southern Wyoming. All supporting data on snowpack properties (mostly modeled) are included to calculate hourly snowpack CO2 fluxes from raw data. In addition, turbulence from the adjacent AmeriFlux eddy covariance scaffold are included for statistical analyses. For comparison purposes, manual CO2 measurements collected at the site from 1998-1999 and 2004-2010 are also included. In addition to data, all scripts are provided to calculate fluxes and determine statistical effects of year, replicate and turbulence on...
U-Pb isotopic data from zircon measured using the SHRIMP-RG ion microprobe at Stanford University, CA. These data are used to calculate absolute ages of the samples from which the zircons were extracted. These samples are shown on the Poncha Pass map being submitted for publication (Minor, et al., in prep)
Data release for: Evaluating k-nearest neighbor (kNN) imputation models for species-level aboveground forest biomass mapping in Northeast China
Quantifying spatially explicit or pixel-level aboveground forest biomass (AFB) across large regions is critical for measuring forest carbon sequestration capacity, assessing forest carbon balance, and revealing changes in the structure and function of forest ecosystems. When AFB is measured at the species level using widely available remote sensing data, regional changes in forest composition can readily be monitored. In this study, wall-to-wall maps of species-level AFB were generated for forests in Northeast China by integrating forest inventory data with Moderate Resolution Imaging Spectroradiometer (MODIS) images and environmental variables through applying the optimal k-nearest neighbor (kNN) imputation model....
Data release for: Spatially explicit reconstruction of post-megafire forest recovery through landscape modeling
This data release provides inputs needed to run the LANDIS PRO forest landscape model and the LINKAGES 3.0 ecosystem process model for the area burned by the Black Dragon Fire in northeast China in 1987, and simulation results that underlie figures and analysis in the accompanying publication. The data release includes the fire perimeter of Great Dragon Fire; input data for LINKAGES including soils, landtype, and climate data; initial conditions of stands in the study area before the Great Dragon Fire; and maps of LANDIS PRO output for each model grid cell including total trees, total biomass (Mg/ha), and tree density (trees/ha) in two-year timesteps.
For use as part of a regional petroleum assessment, the USGS in the early 1990’s developed a dataset reporting elevation on the surface of the Precambrian basement of the central and southern Colorado Plateau and vicinity (Butler, 1991). This dataset was released as paper report that included a table of basement elevations at more than 3,700 control points, including outcrop data of Precambrian rock on the plateau periphery, plus borehole data, seismic data, and depth estimated from a variety of published maps and stratigraphic sections. A contoured map of these data was released as a figure in an interpretive report (Blank and others, 1998). This digital dataset contains spatial datasets corresponding to the elevation...