Todd Hoefen
Todd Hoefen is a Geophysicist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 110
Sample collection of ash and burned soils from the October 2007 southern California Wildfires Sample collection of ash and burned soils from the October 2007 southern California Wildfires
Between November 2 through 9, 2007 scientists from the U.S. Geological Survey (USGS) collected samples of ash and burned soils from 28 sites in six areas burned as a result of the Southern California wildfires of October 2007, including the Harris, Witch, Santiago, Ammo, Canyon, and Grass Valley Fires. The primary goal of this sampling and analysis effort was to understand how...
Authors
Todd M. Hoefen, Raymond F. Kokaly, Deborah A. Martin, Carlton J. Rochester, Geoffrey S. Plumlee, Greg Mendez, Eric G. Reichard, Robert N. Fisher
Inorganic chemical composition and chemical reactivity of settled dust generated by the World Trade Center building collapse 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...
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 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...
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 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...
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
Reflectance spectroscopy of organic compounds: 1. Alkanes Reflectance spectroscopy of organic compounds: 1. Alkanes
Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as...
Authors
R. N. Clark, J. M. Curchin, T.M. Hoefen, G.A. Swayze
Leachate Geochemical Results for Ash Samples from the June 2007 Angora Wildfire Near Lake Tahoe in Northern California Leachate Geochemical Results for Ash Samples from the June 2007 Angora Wildfire Near Lake Tahoe in Northern California
This report releases leachate geochemical data for ash samples produced by the Angora wildfire that burned from June 24 to July 2, 2007, near Lake Tahoe in northern California. The leaching studies are part of a larger interdisciplinary study whose goal is to identify geochemical characteristics and properties of the ash that may adversely affect human health, water quality, air quality...
Authors
Philip L. Hageman, Geoffrey S. Plumlee, Deborah A. Martin, Todd M. Hoefen, Monique Adams, Paul J. Lamothe, Todor I. Todorov, Michael W. Anthony
Science and Products
Filter Total Items: 110
Sample collection of ash and burned soils from the October 2007 southern California Wildfires Sample collection of ash and burned soils from the October 2007 southern California Wildfires
Between November 2 through 9, 2007 scientists from the U.S. Geological Survey (USGS) collected samples of ash and burned soils from 28 sites in six areas burned as a result of the Southern California wildfires of October 2007, including the Harris, Witch, Santiago, Ammo, Canyon, and Grass Valley Fires. The primary goal of this sampling and analysis effort was to understand how...
Authors
Todd M. Hoefen, Raymond F. Kokaly, Deborah A. Martin, Carlton J. Rochester, Geoffrey S. Plumlee, Greg Mendez, Eric G. Reichard, Robert N. Fisher
Inorganic chemical composition and chemical reactivity of settled dust generated by the World Trade Center building collapse 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...
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 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...
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 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...
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
Reflectance spectroscopy of organic compounds: 1. Alkanes Reflectance spectroscopy of organic compounds: 1. Alkanes
Reflectance spectra of the organic compounds comprising the alkane series are presented from the ultraviolet to midinfrared, 0.35 to 15.5 /??m. Alkanes are hydrocarbon molecules containing only single carbon-carbon bonds, and are found naturally on the Earth and in the atmospheres of the giant planets and Saturn's moon, Titan. This paper presents the spectral properties of the alkanes as...
Authors
R. N. Clark, J. M. Curchin, T.M. Hoefen, G.A. Swayze
Leachate Geochemical Results for Ash Samples from the June 2007 Angora Wildfire Near Lake Tahoe in Northern California Leachate Geochemical Results for Ash Samples from the June 2007 Angora Wildfire Near Lake Tahoe in Northern California
This report releases leachate geochemical data for ash samples produced by the Angora wildfire that burned from June 24 to July 2, 2007, near Lake Tahoe in northern California. The leaching studies are part of a larger interdisciplinary study whose goal is to identify geochemical characteristics and properties of the ash that may adversely affect human health, water quality, air quality...
Authors
Philip L. Hageman, Geoffrey S. Plumlee, Deborah A. Martin, Todd M. Hoefen, Monique Adams, Paul J. Lamothe, Todor I. Todorov, Michael W. Anthony