Robert J Horton, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 35
Colorado River Basin Actionable and Strategic Integrated Science and Technology (ASIST) Colorado River Basin Actionable and Strategic Integrated Science and Technology (ASIST)
IntroductionThe U.S. Geological Survey (USGS) is initiating a study approach focused on building cross-disciplinary connections to weave together the scientific knowledge related to drought conditions and effects in the Colorado River Basin. The basin is experiencing the worst drought in recorded history, posing unprecedented new challenges in the basin and in areas relying on water from...
Authors
Katharine G. Dahm, Daniel K. Jones, Patrick J. Anderson, Meghan C. Dick, Todd Hawbaker, Robert Horton
Rocky Mountain Region Science Exchange 2020—EarthMAP and the Colorado River Basin Rocky Mountain Region Science Exchange 2020—EarthMAP and the Colorado River Basin
The U.S. Geological Survey (USGS) Rocky Mountain Region (RMR) hosted USGS scientists, managers, program coordinators, and leadership team members for a virtual Science Exchange during September 15–17, 2020. The Science Exchange had 216 registered participants and included 48 talks over the 3-day period. Invited speakers presented information about the novel USGS Earth Monitoring...
Authors
Anne C. Tillery, Patrick J. Anderson, William J. Andrews, Katharine Dahm, Seth S. Haines, Robert Horton, David O'Leary, Ryan D. Taylor, Kathryn A. Thomas, Alicia Torregrosa
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center, New Mexico Water Science Center, Oklahoma-Texas Water Science Center, Southwest Biological Science Center, Utah Water Science Center, Western Geographic Science Center, Colorado River Basin: Actionable and Strategic Integrated Science and Technology
Use case development for earth monitoring, analysis, and prediction (EarthMAP)—A road map for future integrated predictive science at the U.S. Geological Survey Use case development for earth monitoring, analysis, and prediction (EarthMAP)—A road map for future integrated predictive science at the U.S. Geological Survey
Executive SummaryThe U.S. Geological Survey (USGS) 21st-century science strategy 2020–30 promotes a bureau-wide strategy to develop and deliver an integrated, predictive science capability that works at the scales and timelines needed to inform societally relevant resource management and protection and public safety and environmental health decisions (U.S. Geological Survey, 2021). This...
Authors
Tamara Wilson, Mark T. Wiltermuth, Karen E. Jenni, Robert Horton, Randall J. Hunt, Dee M. Williams, Vivian P. Nolan, Nicholas G. Aumen, David S. Brown, Kyle W. Blasch, Peter S. Murdoch
Using nuclear magnetic resonance and transient electromagnetics to characterise water distribution beneath an ice covered volcanic crater: The case of Sherman Crater Mt. Baker Washington. Using nuclear magnetic resonance and transient electromagnetics to characterise water distribution beneath an ice covered volcanic crater: The case of Sherman Crater Mt. Baker Washington.
Surface and laboratory Nuclear Magnetic Resonance (NMR) measurements combined with transient electromagnetic (TEM) data are powerful tools for subsurface water detection. Surface NMR (sNMR) and TEM soundings, laboratory NMR, complex resistivity, and X-Ray Diffraction (XRD) analysis were all conducted to characterise the distribution of water within Sherman Crater on Mt. Baker, WA. Clay...
Authors
Trevor P. Irons, Kathryn Martin, Carol A. Finn, Benjamin R. Bloss, Robert Horton
Whole rock geochemistry and grain-size analyses from sediment and rock near Tuba City Open Dump, Tuba City, Arizona Whole rock geochemistry and grain-size analyses from sediment and rock near Tuba City Open Dump, Tuba City, Arizona
This report releases new information on grain-size distribution and whole rock geochemistry from samples collected in 2008 in and around Tuba City Open Dump, Tuba City, Arizona.
Authors
Raymond H. Johnson, Valerie K. Stucker, Robert Horton, James K. Otton
234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona 234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona
This report releases 234U/238U isotope data, expressed as activity ratios, and uranium concentration data from analyses completed at Northern Arizona University for groundwater and solid-phase leachate samples that were collected in and around Tuba City Open Dump, Tuba City, Arizona, in 2008.
Authors
Raymond H. Johnson, Robert Horton, James K. Otton, Michael K. Ketterer
Phase and amplitude inversion of crosswell radar data Phase and amplitude inversion of crosswell radar data
Phase and amplitude inversion of crosswell radar data estimates the logarithm of complex slowness for a 2.5D heterogeneous model. The inversion is formulated in the frequency domain using the vector Helmholtz equation. The objective function is minimized using a back-propagation method that is suitable for a 2.5D model and that accounts for the near-, intermediate-, and far-field regions...
Authors
Karl J. Ellefsen, Aldo T. Mazzella, Robert Horton, Jason R. McKenna
Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah: Indications of contaminant migration Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah: Indications of contaminant migration
The Fry Canyon uranium/copper project site in San Juan County, southeastern Utah, was affected by the historical (1957–68) processing of uranium and copper-uranium ores. Relict uranium tailings and related ponds, and a large copper heap-leach pile at the site represent point sources of uranium and copper to local soils, surface water, and groundwater. This study was designed to establish...
Authors
James K. Otton, Robert A. Zielinski, Robert Horton
High-Frequency, Crosswell Radar Data Collected in a Laboratory Tank High-Frequency, Crosswell Radar Data Collected in a Laboratory Tank
Crosswell radar data were collected among three wells in a laboratory tank filled with dry sand. Embedded within the sand was a long plastic box, which was the target for the data collection. Two datasets were collected between each pair of wells, making a total of six datasets. The frequencies in the data ranged from 0.5 to 1.5 gigahertz, and the peak frequency was 0.9 gigahertz. The...
Authors
Bas Peters, Craig W. Moulton, Karl J. Ellefsen, Robert Horton, Jason R. McKenna
Frequency domain, waveform inversion of laboratory crosswell radar data Frequency domain, waveform inversion of laboratory crosswell radar data
A new waveform inversion for crosswell radar is formulated in the frequency-domain for a 2.5D model. The inversion simulates radar waves using the vector Helmholtz equation for electromagnetic waves. The objective function is minimized using a backpropagation method suitable for a 2.5D model. The inversion is tested by processing crosswell radar data collected in a laboratory tank. The...
Authors
Karl J. Ellefsen, Aldo T. Mazzella, Robert Horton, Jason R. McKenna
Results and Interpretations of U.S. Geological Survey Data Collected In and Around the Tuba City Open Dump, Arizona Results and Interpretations of U.S. Geological Survey Data Collected In and Around the Tuba City Open Dump, Arizona
This Open-File Report was originally an Administrative Report presentation to the Bureau of Indian Affairs based on U.S. Geological Survey data that has been collected and presented in four previous reports (Open-File Reports 2009-1020, 2008-1380, and 2008-1374, and an Administrative Report on geophysical data). This presentation was given at a technical meeting requested by the BIA on...
Authors
Raymond H. Johnson, James K. Otton, Robert Horton
Geologic Maps and Cross Sections of the Tuba City Open Dump Site and Vicinity, With Implications for the Occurrence and Flow of Ground Water Geologic Maps and Cross Sections of the Tuba City Open Dump Site and Vicinity, With Implications for the Occurrence and Flow of Ground Water
This report is designed to make available to interested parties geologic and limited hydrologic and geochemical information about the Tuba City Open Dump (TCOD) site. This information has been gathered during studies of the site from January to September 2008. Mapping by the authors and construction of cross sections show that a section of gently northeast-dipping Jurassic sedimentary...
Authors
James K. Otton, Ray H. Johnson, Robert Horton
Science and Products
Filter Total Items: 35
Colorado River Basin Actionable and Strategic Integrated Science and Technology (ASIST) Colorado River Basin Actionable and Strategic Integrated Science and Technology (ASIST)
IntroductionThe U.S. Geological Survey (USGS) is initiating a study approach focused on building cross-disciplinary connections to weave together the scientific knowledge related to drought conditions and effects in the Colorado River Basin. The basin is experiencing the worst drought in recorded history, posing unprecedented new challenges in the basin and in areas relying on water from...
Authors
Katharine G. Dahm, Daniel K. Jones, Patrick J. Anderson, Meghan C. Dick, Todd Hawbaker, Robert Horton
Rocky Mountain Region Science Exchange 2020—EarthMAP and the Colorado River Basin Rocky Mountain Region Science Exchange 2020—EarthMAP and the Colorado River Basin
The U.S. Geological Survey (USGS) Rocky Mountain Region (RMR) hosted USGS scientists, managers, program coordinators, and leadership team members for a virtual Science Exchange during September 15–17, 2020. The Science Exchange had 216 registered participants and included 48 talks over the 3-day period. Invited speakers presented information about the novel USGS Earth Monitoring...
Authors
Anne C. Tillery, Patrick J. Anderson, William J. Andrews, Katharine Dahm, Seth S. Haines, Robert Horton, David O'Leary, Ryan D. Taylor, Kathryn A. Thomas, Alicia Torregrosa
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center, New Mexico Water Science Center, Oklahoma-Texas Water Science Center, Southwest Biological Science Center, Utah Water Science Center, Western Geographic Science Center, Colorado River Basin: Actionable and Strategic Integrated Science and Technology
Use case development for earth monitoring, analysis, and prediction (EarthMAP)—A road map for future integrated predictive science at the U.S. Geological Survey Use case development for earth monitoring, analysis, and prediction (EarthMAP)—A road map for future integrated predictive science at the U.S. Geological Survey
Executive SummaryThe U.S. Geological Survey (USGS) 21st-century science strategy 2020–30 promotes a bureau-wide strategy to develop and deliver an integrated, predictive science capability that works at the scales and timelines needed to inform societally relevant resource management and protection and public safety and environmental health decisions (U.S. Geological Survey, 2021). This...
Authors
Tamara Wilson, Mark T. Wiltermuth, Karen E. Jenni, Robert Horton, Randall J. Hunt, Dee M. Williams, Vivian P. Nolan, Nicholas G. Aumen, David S. Brown, Kyle W. Blasch, Peter S. Murdoch
Using nuclear magnetic resonance and transient electromagnetics to characterise water distribution beneath an ice covered volcanic crater: The case of Sherman Crater Mt. Baker Washington. Using nuclear magnetic resonance and transient electromagnetics to characterise water distribution beneath an ice covered volcanic crater: The case of Sherman Crater Mt. Baker Washington.
Surface and laboratory Nuclear Magnetic Resonance (NMR) measurements combined with transient electromagnetic (TEM) data are powerful tools for subsurface water detection. Surface NMR (sNMR) and TEM soundings, laboratory NMR, complex resistivity, and X-Ray Diffraction (XRD) analysis were all conducted to characterise the distribution of water within Sherman Crater on Mt. Baker, WA. Clay...
Authors
Trevor P. Irons, Kathryn Martin, Carol A. Finn, Benjamin R. Bloss, Robert Horton
Whole rock geochemistry and grain-size analyses from sediment and rock near Tuba City Open Dump, Tuba City, Arizona Whole rock geochemistry and grain-size analyses from sediment and rock near Tuba City Open Dump, Tuba City, Arizona
This report releases new information on grain-size distribution and whole rock geochemistry from samples collected in 2008 in and around Tuba City Open Dump, Tuba City, Arizona.
Authors
Raymond H. Johnson, Valerie K. Stucker, Robert Horton, James K. Otton
234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona 234U/238U isotope data from groundwater and solid-phase leachate samples near Tuba City Open Dump, Tuba City, Arizona
This report releases 234U/238U isotope data, expressed as activity ratios, and uranium concentration data from analyses completed at Northern Arizona University for groundwater and solid-phase leachate samples that were collected in and around Tuba City Open Dump, Tuba City, Arizona, in 2008.
Authors
Raymond H. Johnson, Robert Horton, James K. Otton, Michael K. Ketterer
Phase and amplitude inversion of crosswell radar data Phase and amplitude inversion of crosswell radar data
Phase and amplitude inversion of crosswell radar data estimates the logarithm of complex slowness for a 2.5D heterogeneous model. The inversion is formulated in the frequency domain using the vector Helmholtz equation. The objective function is minimized using a back-propagation method that is suitable for a 2.5D model and that accounts for the near-, intermediate-, and far-field regions...
Authors
Karl J. Ellefsen, Aldo T. Mazzella, Robert Horton, Jason R. McKenna
Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah: Indications of contaminant migration Geology, geochemistry, and geophysics of the Fry Canyon uranium/copper project site, southeastern Utah: Indications of contaminant migration
The Fry Canyon uranium/copper project site in San Juan County, southeastern Utah, was affected by the historical (1957–68) processing of uranium and copper-uranium ores. Relict uranium tailings and related ponds, and a large copper heap-leach pile at the site represent point sources of uranium and copper to local soils, surface water, and groundwater. This study was designed to establish...
Authors
James K. Otton, Robert A. Zielinski, Robert Horton
High-Frequency, Crosswell Radar Data Collected in a Laboratory Tank High-Frequency, Crosswell Radar Data Collected in a Laboratory Tank
Crosswell radar data were collected among three wells in a laboratory tank filled with dry sand. Embedded within the sand was a long plastic box, which was the target for the data collection. Two datasets were collected between each pair of wells, making a total of six datasets. The frequencies in the data ranged from 0.5 to 1.5 gigahertz, and the peak frequency was 0.9 gigahertz. The...
Authors
Bas Peters, Craig W. Moulton, Karl J. Ellefsen, Robert Horton, Jason R. McKenna
Frequency domain, waveform inversion of laboratory crosswell radar data Frequency domain, waveform inversion of laboratory crosswell radar data
A new waveform inversion for crosswell radar is formulated in the frequency-domain for a 2.5D model. The inversion simulates radar waves using the vector Helmholtz equation for electromagnetic waves. The objective function is minimized using a backpropagation method suitable for a 2.5D model. The inversion is tested by processing crosswell radar data collected in a laboratory tank. The...
Authors
Karl J. Ellefsen, Aldo T. Mazzella, Robert Horton, Jason R. McKenna
Results and Interpretations of U.S. Geological Survey Data Collected In and Around the Tuba City Open Dump, Arizona Results and Interpretations of U.S. Geological Survey Data Collected In and Around the Tuba City Open Dump, Arizona
This Open-File Report was originally an Administrative Report presentation to the Bureau of Indian Affairs based on U.S. Geological Survey data that has been collected and presented in four previous reports (Open-File Reports 2009-1020, 2008-1380, and 2008-1374, and an Administrative Report on geophysical data). This presentation was given at a technical meeting requested by the BIA on...
Authors
Raymond H. Johnson, James K. Otton, Robert Horton
Geologic Maps and Cross Sections of the Tuba City Open Dump Site and Vicinity, With Implications for the Occurrence and Flow of Ground Water Geologic Maps and Cross Sections of the Tuba City Open Dump Site and Vicinity, With Implications for the Occurrence and Flow of Ground Water
This report is designed to make available to interested parties geologic and limited hydrologic and geochemical information about the Tuba City Open Dump (TCOD) site. This information has been gathered during studies of the site from January to September 2008. Mapping by the authors and construction of cross sections show that a section of gently northeast-dipping Jurassic sedimentary...
Authors
James K. Otton, Ray H. Johnson, Robert Horton