Publications
Products (journal articles, reports, fact sheets) authored by current and past scientists are listed below. Please check the USGS Pubs Warehouse for other USGS publications.
Filter Total Items: 1826
40Ar/39Ar dates for the Spanish Peaks intrusions in south-central Colorado
A diverse suite of spatially and temporally juxtaposed igneous rocks ranging from alkaline lamprophyres to granites intruded south-central Colorado during late Oligocene and early Miocene time. In addition to the stocks of the East and West Spanish Peaks, there are three types of dikes exposed in the region, based on orientation: radial, subparallel (striking approximately east–west), and independ
Authors
B.S. Penn, David A. Lindsey
Ground-Water Temperature, Noble Gas, and Carbon Isotope Data from the Espanola Basin, New Mexico
Ground-water samples were collected from 56 locations throughout the Espanola Basin and analyzed for general chemistry (major ions and trace elements), carbon isotopes (delta 13C and 14C activity) in dissolved inorganic carbon, noble gases (He, Ne, Ar, Kr, Xe, and 3He/4He ratio), and tritium. Temperature profiles were measured at six locations in the southeastern part of the basin. Temperature pro
Authors
Andrew H. Manning
Quaternary incision rates and drainage evolution of the Uncompahgre and Gunnison Rivers, western Colorado, as calibrated by the Lava Creek B ash
The Quaternary erosional history of western Colorado is documented in terraces of the Colorado, Gunnison, and Uncompahgre Rivers that contain the Lava Creek B ash (0.64 Ma). This paper reports an important new ash locality that dates ca. 100-m-high river gravels associated with the paleo-confluence of the Gunnison and Uncompahgre Rivers upstream from Grand Junction. Provenance analysis reveals pal
Authors
Andrew L. Darling, Karl E. Karlstrom, Andres Aslan, Rex D. Cole, Charles Betton, Elmira Wan
Inorganic chemical composition and chemical reactivity of settled dust generated by the World Trade Center building collapse
Samples of dust deposited around lower Manhattan by the September 11, 2001, World Trade Center (WTC) collapse have inorganic chemical compositions that result in part from the variable chemical contributions of concrete, gypsum wallboard, glass fibers, window glass, and other materials contained in the buildings. The dust deposits were also modified chemically by variable interactions with rain wa
Authors
Geoffrey S. Plumlee, Philip L. Hageman, Paul J. Lamothe, Thomas L. Ziegler, Gregory P. Meeker, Peter M. Theodorakos, Isabelle Brownfield, Monique G. Adams, Gregg A. Swayze, Todd M. Hoefen, Joseph E. Taggart, Roger N. Clark, S. Wilson, Stephen J. Sutley
Materials characterization of dusts generated by the collapse of the World Trade Center
The major inorganic components of the dusts generated from the collapse of the World Trade Center buildings on September 11, 2001 were concrete materials, gypsum, and man-made vitreous fibers. These components were likely derived from lightweight Portland cement concrete floors, gypsum wallboard, and spray-on fireproofing and ceiling tiles, respectively. All of the 36 samples collected by the USGS
Authors
Gregory P. Meeker, Stephen J. Sutley, Isabelle Brownfield, Heather Lowers, Amy M. Bern, Gregg A. Swayze, Todd M. Hoefen, Geoffrey S. Plumlee, Roger N. Clark, Carol A. Gent
Environmental mapping of the World Trade Center area with imaging spectroscopy after the September 11, 2001 attack
The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) was flown over the World Trade Center area on September 16, 18, 22, and 23, 2001. The data were used to map the WTC debris plume and its contents, including the spectral signatures of asbestiform minerals. Samples were collected and used as ground truth for the AVARIS mapping. A number of thermal hot spots were observed with temperatures
Authors
Roger N. Clark, Gregg A. Swayze, Todd M. Hoefen, Robert O. Green, Keith E. Livo, Gregory P. Meeker, Stephen J. Sutley, Geoffrey S. Plumlee, Betina Pavri, Charles M. Sarture, Joe Boardman, Isabelle Brownfield, Laurie C. Morath
A comparison of phase inversion and traveltime tomography for processing near-surface refraction traveltimes
With phase inversion, one can estimate subsurface velocities using the phases of first-arriving waves, which are the frequency-domain equivalents of the traveltimes. Phase inversion is modified to make it suitable for processing traveltimes from near-surface refraction surveys. The modifications include parameterizing the model, correcting the observed phases, and selecting the complex frequency.
Authors
Karl J. Ellefsen