Pb isotope measurements of road dusts and background geologic materials in the Viburnum Trend resource extraction area of southeast Missouri (2011)
Abstract The isotopic composition of Pb in fugitive dust suspended by a vehicle from 13 unsurfaced roads in Missouri was measured to identify the source of Pb within an established long-term mining area. A three end member model using 207Pb/206Pb and concentration as tracers resulted in fugitive dust samples plotting in the mixing field of well characterized heterogeneous end members. End members selected for this investigation include the 207Pb/206Pb for 1) a Pb-mixture representing mine tailings, 2) aerosol Pb impacted soils within close proximity to the Buick secondary recycling smelter, and 3) an average of soils, rock cores and drill cuttings representing the background characteristics. Aqua regia total concentrations...
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.
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...
GAP species range data are coarse representations of the total areal extent a species occupies, in other words the geographic limits within which a species can be found (Morrison and Hall 2002). These data provide the geographic extent within which the USGS Gap Analysis Project delineates areas of suitable habitat for terrestrial vertebrate species in their species' habitat maps. The range maps are created by attributing a vector file derived from the 12-digit Hydrologic Unit Dataset (USDA NRCS 2009). Modifications to that dataset are described here. Attribution of the season range for each species was based on the literature and online sources (See Cross Reference section of the metadata). Attribution for each...