Paul A Bedrosian
Paul is an expert in the development and application of electromagnetic geophysical methods to framework tectonics, resource assessment, natural hazards and fundamental Earth processes. His work has investigated seismic variability along the San Andreas Fault, tectonics of the Pacific Northwest and Upper Midwest, and the structure of Mount St. Helens. His current research is on regional-scale mine
Research Interests
- Structure and evolution of active and fossil tectonic margins
- Geophysical imaging of hydrothermal and magmatic systems
- Joint interpretation of coincident geophysical data sets
- Advanced processing and modeling techniques for imaging earth structure
Professional Experience
2008-present, Research Geophysicist, U.S. Geological Survey, Denver, Colorado
2005-2007, Mendenhall Fellow, U.S Geological Survey, Denver, Colorado
2002-2004, Humboldt Fellow, GeoForschungsZentrum, Potsdam Germany
1998-2002, Research Assistant, University of Washington, Seattle, Washington
Education and Certifications
Ph.D. Physics, University of Washington, 2002
M.S. Physics, University of Washington, 1998
B.S. Physics, University Of Minnesota, 1996
B.S. Chemistry, University of Minnesota, 1996
Affiliations and Memberships*
2010-present, Summer of Applied Geophysical Experience (faculty)
2018-present, Earth, Planets and Space Journal (editor)
American Geophysical Union
Geological Society of America
Science and Products
Filter Total Items: 13
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Filter Total Items: 83
Integrated geophysical imaging of a concealed mineral deposit: a case study of the world-class Pebble porphyry deposit in southwestern Alaska Integrated geophysical imaging of a concealed mineral deposit: a case study of the world-class Pebble porphyry deposit in southwestern Alaska
We combined aeromagnetic, induced polarization, magnetotelluric, and gravity surveys as well as drillhole geologic, alteration, magnetic susceptibility, and density data for exploration and characterization of the Cu-Au-Mo Pebble porphyry deposit. This undeveloped deposit is almost completely concealed by postmineralization sedimentary and volcanic rocks, presenting an exploration...
Authors
Anjana K. Shah, Paul A. Bedrosian, Eric D. Anderson, Karen D. Kelley, James Lang
Advancements in understanding the aeromagnetic expressions of basin-margin faults—An example from San Luis Basin, Colorado Advancements in understanding the aeromagnetic expressions of basin-margin faults—An example from San Luis Basin, Colorado
Advancements in aeromagnetic acquisition technology over the past few decades have led to greater resolution of shallow geologic sources with low magnetization, such as intrasedimentary faults and paleochannels. Detection and mapping of intrasedimentary faults in particular can be important for understanding the overall structural setting of an area, even if exploration targets are much...
Authors
V. J. Grauch, Paul A. Bedrosian, Benjamin J. Drenth
Geological analysis of aeromagnetic data from southwestern Alaska: Implications for exploration in the area of the Pebble porphyry Cu-Au-Mo deposit Geological analysis of aeromagnetic data from southwestern Alaska: Implications for exploration in the area of the Pebble porphyry Cu-Au-Mo deposit
Aeromagnetic data are used to better understand the geology and mineral resources near the Late Cretaceous Pebble porphyry Cu-Au-Mo deposit in southwestern Alaska. The reduced-to-pole (RTP) transformation of regional-scale aeromagnetic data shows that the Pebble deposit is within a cluster of magnetic anomaly highs. Similar to Pebble, the Iliamna, Kijik, and Neacola porphyry copper...
Authors
Eric D. Anderson, Murray W. Hitzman, Thomas Monecke, Paul A. Bedrosian, Anjana K. Shah, Karen D. Kelley
Faulting and groundwater in a desert environment: constraining hydrogeology using time-domain electromagnetic data Faulting and groundwater in a desert environment: constraining hydrogeology using time-domain electromagnetic data
Within the south-western Mojave Desert, the Joshua Basin Water District is considering applying imported water into infiltration ponds in the Joshua Tree groundwater sub-basin in an attempt to artificially recharge the underlying aquifer. Scarce subsurface hydrogeological data are available near the proposed recharge site; therefore, time-domain electromagnetic (TDEM) data were collected...
Authors
Paul A. Bedrosian, Matthew K. Burgess, Tracy Nishikawa
Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA
Ice-thickness measurements critical for flood and mudflow hazard studies are very sparse on Cascade Range (North America) volcanoes. Helicopter electromagnetic (HEM) data collected to detect hydrothermal alteration are used to determine ice thickness over portions of Mount Baker and Mount Adams volcanoes. A laterally continuous inversion method provides good estimates of ice
Authors
Carol A. Finn, Maria Deszcz-Pan, Paul A. Bedrosian
Hydrostratigraphic interpretation of test-hole and surface geophysical data, Elkhorn and Loup River Basins, Nebraska, 2008 to 2011 Hydrostratigraphic interpretation of test-hole and surface geophysical data, Elkhorn and Loup River Basins, Nebraska, 2008 to 2011
The Elkhorn-Loup Model (ELM) was begun in 2006 to understand the effect of various groundwater-management scenarios on surface-water resources. During phase one of the ELM study, a lack of subsurface geological information was identified as a data gap. Test holes drilled to the base of the aquifer in the ELM study area are spaced as much as 25 miles apart, especially in areas of the...
Authors
Christopher M. Hobza, Paul A. Bedrosian, Benjamin R. Bloss
Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska
Airborne geophysical surveys of selected areas of the North and South Platte River valleys of Nebraska, including Lodgepole Creek valley, collected data to map aquifers and bedrock topography and thus improve the understanding of groundwater - surface-water relationships to be used in water-management decisions. Frequency-domain helicopter electromagnetic surveys, using a unique survey...
Authors
Jared D. Abraham, James C. Cannia, Paul A. Bedrosian, Michaela R. Johnson, Lyndsay B. Ball, Steven S. Sibray
Evaluation of geophysical techniques for the detection of paleochannels in the Oakland area of eastern Nebraska as part of the Eastern Nebraska Water Resource Assessment Evaluation of geophysical techniques for the detection of paleochannels in the Oakland area of eastern Nebraska as part of the Eastern Nebraska Water Resource Assessment
Over the winter and spring of 2009, the U.S. Geological Survey conducted a general assessment of the capabilities of several geophysical tools to delineate buried paleochannel aquifers in the glacial terrain of eastern Nebraska. Mapping these paleochannels is an important objective for the Eastern Nebraska Water Resources Assessment group. Previous attempts at mapping these channels...
Authors
Jared D. Abraham, Paul A. Bedrosian, Theodore H. Asch, Lyndsay B. Ball, James C. Cannia, Jeffery D. Phillips, Susan Lackey
Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California
A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design...
Authors
P. A. Bedrosian, B.L. Burton, M.H. Powers, B. J. Minsley, J. D. Phillips, L. E. Hunter
Geophysical, geochemical, and mineralogical data from the Pebble Cu-Au-Mo porphyry deposit area, southwest Alaska: Contributions to assessment techniques for concealed mineral resources Geophysical, geochemical, and mineralogical data from the Pebble Cu-Au-Mo porphyry deposit area, southwest Alaska: Contributions to assessment techniques for concealed mineral resources
In 2007, the U.S. Geological Survey began a multidisciplinary study in southwest Alaska to investigate the setting and detectability of mineral deposits in concealed volcanic and glacial terranes. The study area hosts the world-class Pebble porphyry Cu-Au-Mo deposit, and through collaboration with the Pebble Limited Partnership, a range of geophysical and geochemical investigations was...
Authors
E. D. Anderson, S. M. Smith, S. A. Giles, Matthew Granitto, R. G. Eppinger, P. A. Bedrosian, A. K. Shah, K.D. Kelley, D.L. Fey, B. J. Minsley, P. J. Brown
Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments
In the framework of the DEad SEa Rift Transect (DESERT) project a 150 km magnetotelluric profile consisting of 154 sites was carried out across the Dead Sea Transform. The resistivity model presented shows conductive structures in the western section of the study area terminating abruptly at the Arava Fault. For a more detailed analysis we performed a joint interpretation of the...
Authors
J. Stankiewicz, G. Munoz, O. Ritter, Paul A. Bedrosian, T. Ryberg, U. Weckmann, M. Weber
Correlation between deep fluids, tremor and creep along the central San Andreas fault Correlation between deep fluids, tremor and creep along the central San Andreas fault
The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from...
Authors
M. Becken, O. Ritter, P. A. Bedrosian, U. Weckmann
Non-USGS Publications**
P.A. Bedrosian, M.J. Unsworth, G.D. Egbert and C.H. Thurber. 2004. Geophysical images of the creeping San Andreas Fault: Implications for the role of crustal fluids in the earthquake process, Tectonophys., 385(1-4), doi:10.1016/j.tecto.2004.02.010.
M.J. Unsworth and P.A. Bedrosian. 2004. Electrical resistivity structure at the SAFOD site from magnetotelluric exploration, Geophys. Res. Lett., 31(12), doi:10.1029/2003GL019045.
M.J. Unsworth and P.A. Bedrosian. 2004. On the geoelectric structure of major strike-slip faults and shear zones., Earth, Planets and Space, 56, 1177–1184, doi:10.1186/BF03353337.
M.J. Unsworth, W. Wenbo, A. G. Jones, S. Li, P.A. Bedrosian, J. Booker, J. Sheng, D. Ming and T. Handong. 2004. Crustal and upper mantle structure of Northern Tibet imaged with magnetotelluric data, J. Geophys. Res., 109, doi:10.1029/2002JB002305.
P.A. Bedrosian, M.J. Unsworth and G.D. Egbert. 2002. Magnetotelluric imaging of the creeping segment of the San Andreas Fault near Hollister, Geophys. Res. Lett., 29(11), 1506, doi:10.1029/2001GL014119.
M. Unsworth, O.C. Enriquez, S. Belmonte, J. Arzate and P.A. Bedrosian. 2002. Crustal structure of the Chicxulub Impact Crater imaged with magnetotelluric exploration, Geophys. Res. Lett., 29(16), 1788, doi:10.1029/2002GL014998.
P.A. Bedrosian, M.J. Unsworth and F. Wang. 2001. Structure of the Altyn Tagh Fault and Daxue Shan from magnetotelluric surveys: Implications for faulting associated with the rise of the Tibetan Plateau, Tectonics, 20, 474-486, doi:10.1029/2000TC001215.
W. Wenbo, M. Unsworth, A. Jones, J. Booker, H. Tan, D. Nelson, L. Chen, S. Li, K. Solon, P.A. Bedrosian, S. Jin, M. Deng, J. Ledo, D. Kay and B. Roberts. 2001. Widespread fluids in the Tibetan Crust, Science, 292(5517), 716-718, doi:10.1126/science.1010580.
M. Unsworth, P.A. Bedrosian, M. Eisel, G. Egbert and W. Siripunvaraporn. 2000. Along-strike variations in the electrical structure of the San Andreas Fault at Parkfield, California, Geophys. Res. Lett., 27(18), 3021-3024, doi:10.1029/2000GL011476.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 13
No Result Found
Filter Total Items: 83
Integrated geophysical imaging of a concealed mineral deposit: a case study of the world-class Pebble porphyry deposit in southwestern Alaska Integrated geophysical imaging of a concealed mineral deposit: a case study of the world-class Pebble porphyry deposit in southwestern Alaska
We combined aeromagnetic, induced polarization, magnetotelluric, and gravity surveys as well as drillhole geologic, alteration, magnetic susceptibility, and density data for exploration and characterization of the Cu-Au-Mo Pebble porphyry deposit. This undeveloped deposit is almost completely concealed by postmineralization sedimentary and volcanic rocks, presenting an exploration...
Authors
Anjana K. Shah, Paul A. Bedrosian, Eric D. Anderson, Karen D. Kelley, James Lang
Advancements in understanding the aeromagnetic expressions of basin-margin faults—An example from San Luis Basin, Colorado Advancements in understanding the aeromagnetic expressions of basin-margin faults—An example from San Luis Basin, Colorado
Advancements in aeromagnetic acquisition technology over the past few decades have led to greater resolution of shallow geologic sources with low magnetization, such as intrasedimentary faults and paleochannels. Detection and mapping of intrasedimentary faults in particular can be important for understanding the overall structural setting of an area, even if exploration targets are much...
Authors
V. J. Grauch, Paul A. Bedrosian, Benjamin J. Drenth
Geological analysis of aeromagnetic data from southwestern Alaska: Implications for exploration in the area of the Pebble porphyry Cu-Au-Mo deposit Geological analysis of aeromagnetic data from southwestern Alaska: Implications for exploration in the area of the Pebble porphyry Cu-Au-Mo deposit
Aeromagnetic data are used to better understand the geology and mineral resources near the Late Cretaceous Pebble porphyry Cu-Au-Mo deposit in southwestern Alaska. The reduced-to-pole (RTP) transformation of regional-scale aeromagnetic data shows that the Pebble deposit is within a cluster of magnetic anomaly highs. Similar to Pebble, the Iliamna, Kijik, and Neacola porphyry copper...
Authors
Eric D. Anderson, Murray W. Hitzman, Thomas Monecke, Paul A. Bedrosian, Anjana K. Shah, Karen D. Kelley
Faulting and groundwater in a desert environment: constraining hydrogeology using time-domain electromagnetic data Faulting and groundwater in a desert environment: constraining hydrogeology using time-domain electromagnetic data
Within the south-western Mojave Desert, the Joshua Basin Water District is considering applying imported water into infiltration ponds in the Joshua Tree groundwater sub-basin in an attempt to artificially recharge the underlying aquifer. Scarce subsurface hydrogeological data are available near the proposed recharge site; therefore, time-domain electromagnetic (TDEM) data were collected...
Authors
Paul A. Bedrosian, Matthew K. Burgess, Tracy Nishikawa
Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA Helicopter electromagnetic data map ice thickness at Mount Adams and Mount Baker, Washington, USA
Ice-thickness measurements critical for flood and mudflow hazard studies are very sparse on Cascade Range (North America) volcanoes. Helicopter electromagnetic (HEM) data collected to detect hydrothermal alteration are used to determine ice thickness over portions of Mount Baker and Mount Adams volcanoes. A laterally continuous inversion method provides good estimates of ice
Authors
Carol A. Finn, Maria Deszcz-Pan, Paul A. Bedrosian
Hydrostratigraphic interpretation of test-hole and surface geophysical data, Elkhorn and Loup River Basins, Nebraska, 2008 to 2011 Hydrostratigraphic interpretation of test-hole and surface geophysical data, Elkhorn and Loup River Basins, Nebraska, 2008 to 2011
The Elkhorn-Loup Model (ELM) was begun in 2006 to understand the effect of various groundwater-management scenarios on surface-water resources. During phase one of the ELM study, a lack of subsurface geological information was identified as a data gap. Test holes drilled to the base of the aquifer in the ELM study area are spaced as much as 25 miles apart, especially in areas of the...
Authors
Christopher M. Hobza, Paul A. Bedrosian, Benjamin R. Bloss
Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska Airborne electromagnetic mapping of the base of aquifer in areas of western Nebraska
Airborne geophysical surveys of selected areas of the North and South Platte River valleys of Nebraska, including Lodgepole Creek valley, collected data to map aquifers and bedrock topography and thus improve the understanding of groundwater - surface-water relationships to be used in water-management decisions. Frequency-domain helicopter electromagnetic surveys, using a unique survey...
Authors
Jared D. Abraham, James C. Cannia, Paul A. Bedrosian, Michaela R. Johnson, Lyndsay B. Ball, Steven S. Sibray
Evaluation of geophysical techniques for the detection of paleochannels in the Oakland area of eastern Nebraska as part of the Eastern Nebraska Water Resource Assessment Evaluation of geophysical techniques for the detection of paleochannels in the Oakland area of eastern Nebraska as part of the Eastern Nebraska Water Resource Assessment
Over the winter and spring of 2009, the U.S. Geological Survey conducted a general assessment of the capabilities of several geophysical tools to delineate buried paleochannel aquifers in the glacial terrain of eastern Nebraska. Mapping these paleochannels is an important objective for the Eastern Nebraska Water Resources Assessment group. Previous attempts at mapping these channels...
Authors
Jared D. Abraham, Paul A. Bedrosian, Theodore H. Asch, Lyndsay B. Ball, James C. Cannia, Jeffery D. Phillips, Susan Lackey
Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California Geophysical investigations of geology and structure at the Martis Creek Dam, Truckee, California
A recent evaluation of Martis Creek Dam highlighted the potential for dam failure due to either seepage or an earthquake on nearby faults. In 1972, the U.S. Army Corps of Engineers constructed this earthen dam, located within the Truckee Basin to the north of Lake Tahoe, CA for water storage and flood control. Past attempts to raise the level of the Martis Creek Reservoir to its design...
Authors
P. A. Bedrosian, B.L. Burton, M.H. Powers, B. J. Minsley, J. D. Phillips, L. E. Hunter
Geophysical, geochemical, and mineralogical data from the Pebble Cu-Au-Mo porphyry deposit area, southwest Alaska: Contributions to assessment techniques for concealed mineral resources Geophysical, geochemical, and mineralogical data from the Pebble Cu-Au-Mo porphyry deposit area, southwest Alaska: Contributions to assessment techniques for concealed mineral resources
In 2007, the U.S. Geological Survey began a multidisciplinary study in southwest Alaska to investigate the setting and detectability of mineral deposits in concealed volcanic and glacial terranes. The study area hosts the world-class Pebble porphyry Cu-Au-Mo deposit, and through collaboration with the Pebble Limited Partnership, a range of geophysical and geochemical investigations was...
Authors
E. D. Anderson, S. M. Smith, S. A. Giles, Matthew Granitto, R. G. Eppinger, P. A. Bedrosian, A. K. Shah, K.D. Kelley, D.L. Fey, B. J. Minsley, P. J. Brown
Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments
In the framework of the DEad SEa Rift Transect (DESERT) project a 150 km magnetotelluric profile consisting of 154 sites was carried out across the Dead Sea Transform. The resistivity model presented shows conductive structures in the western section of the study area terminating abruptly at the Arava Fault. For a more detailed analysis we performed a joint interpretation of the...
Authors
J. Stankiewicz, G. Munoz, O. Ritter, Paul A. Bedrosian, T. Ryberg, U. Weckmann, M. Weber
Correlation between deep fluids, tremor and creep along the central San Andreas fault Correlation between deep fluids, tremor and creep along the central San Andreas fault
The seismicity pattern along the San Andreas fault near Parkfield and Cholame, California, varies distinctly over a length of only fifty kilometres. Within the brittle crust, the presence of frictionally weak minerals, fault-weakening high fluid pressures and chemical weakening are considered possible causes of an anomalously weak fault northwest of Parkfield. Non-volcanic tremor from...
Authors
M. Becken, O. Ritter, P. A. Bedrosian, U. Weckmann
Non-USGS Publications**
P.A. Bedrosian, M.J. Unsworth, G.D. Egbert and C.H. Thurber. 2004. Geophysical images of the creeping San Andreas Fault: Implications for the role of crustal fluids in the earthquake process, Tectonophys., 385(1-4), doi:10.1016/j.tecto.2004.02.010.
M.J. Unsworth and P.A. Bedrosian. 2004. Electrical resistivity structure at the SAFOD site from magnetotelluric exploration, Geophys. Res. Lett., 31(12), doi:10.1029/2003GL019045.
M.J. Unsworth and P.A. Bedrosian. 2004. On the geoelectric structure of major strike-slip faults and shear zones., Earth, Planets and Space, 56, 1177–1184, doi:10.1186/BF03353337.
M.J. Unsworth, W. Wenbo, A. G. Jones, S. Li, P.A. Bedrosian, J. Booker, J. Sheng, D. Ming and T. Handong. 2004. Crustal and upper mantle structure of Northern Tibet imaged with magnetotelluric data, J. Geophys. Res., 109, doi:10.1029/2002JB002305.
P.A. Bedrosian, M.J. Unsworth and G.D. Egbert. 2002. Magnetotelluric imaging of the creeping segment of the San Andreas Fault near Hollister, Geophys. Res. Lett., 29(11), 1506, doi:10.1029/2001GL014119.
M. Unsworth, O.C. Enriquez, S. Belmonte, J. Arzate and P.A. Bedrosian. 2002. Crustal structure of the Chicxulub Impact Crater imaged with magnetotelluric exploration, Geophys. Res. Lett., 29(16), 1788, doi:10.1029/2002GL014998.
P.A. Bedrosian, M.J. Unsworth and F. Wang. 2001. Structure of the Altyn Tagh Fault and Daxue Shan from magnetotelluric surveys: Implications for faulting associated with the rise of the Tibetan Plateau, Tectonics, 20, 474-486, doi:10.1029/2000TC001215.
W. Wenbo, M. Unsworth, A. Jones, J. Booker, H. Tan, D. Nelson, L. Chen, S. Li, K. Solon, P.A. Bedrosian, S. Jin, M. Deng, J. Ledo, D. Kay and B. Roberts. 2001. Widespread fluids in the Tibetan Crust, Science, 292(5517), 716-718, doi:10.1126/science.1010580.
M. Unsworth, P.A. Bedrosian, M. Eisel, G. Egbert and W. Siripunvaraporn. 2000. Along-strike variations in the electrical structure of the San Andreas Fault at Parkfield, California, Geophys. Res. Lett., 27(18), 3021-3024, doi:10.1029/2000GL011476.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government