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
Magnetotelluric sampling and geoelectric hazard estimation: Are national-scale surveys sufficient?
3-D Modeling of the Duluth Complex from geophysical data
Airborne geophysical imaging of weak zones on Iliamna Volcano, Alaska: Implications for slope stability
Simultaneous observations of geoelectric and geomagnetic fields produced by magnetospheric ULF waves
Quantifying model structural uncertainty using airborne electromagnetic data
High-resolution mapping of the freshwater-brine interface using deterministic and Bayesian inversion of airborne electromagnetic data at Paradox Valley, USA
A 100-year geoelectric hazard analysis for the U.S. high-voltage power grid
Empirical estimation of natural geoelectric hazards
The first 3D conductivity model of the contiguous US: Reflections on geologic structure and application to induction hazards
Crustal magmatism and anisotropy beneath the Arabian Shield - A cautionary tale
Lithospheric signature of late Cenozoic extension in electrical resistivity structure of the Rio Grande rift, New Mexico, USA
Extreme‐value geoelectric amplitude and polarization across the northeast United States
Non-USGS Publications**
**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
- Science
- Data
- Multimedia
- Publications
Filter Total Items: 76
Magnetotelluric sampling and geoelectric hazard estimation: Are national-scale surveys sufficient?
At present, the most reliable information for inferring storm-time ground electric fields along electrical transmission lines comes from coarsely sampled, national-scale magnetotelluric (MT) data sets, such as that provided by the EarthScope USArray program. An underlying assumption in the use of such data is that they adequately sample the spatial heterogeneity of the surface relationship betweenAuthorsBenjamin Scott Murphy, Greg M. Lucas, Jeffrey J. Love, Anna Kelbert, Paul A. Bedrosian, E. Joshua Rigler3-D Modeling of the Duluth Complex from geophysical data
The Mesoproterozoic Duluth Complex in northeastern Minnesota is one of the major plutonic components of the Midcontinent Rift System and hosts a variety of copper-nickel sulfide and platinum-group element deposits. The Duluth Complex is composed of a series of individual mafic and felsic intrusions emplaced 1110-1098 Ma within Paleoproterozoic sedimentary rocks of the Animikie basin and volcanic fAuthorsDana E. Peterson, Paul A. Bedrosian, Carol A. FinnAirborne geophysical imaging of weak zones on Iliamna Volcano, Alaska: Implications for slope stability
Water‐saturated, hydrothermally altered rocks reduce the strength of volcanic edifices and increase the potential for sector collapses and far‐traveled mass flows of unconsolidated debris. Iliamna Volcano is an andesitic stratovolcano located on the western side of the Cook Inlet, ∼225 km southwest of Anchorage and is a source of repeated avalanches. The widespread snow and ice cover on Iliamna VoAuthorsDana E. Peterson, Carol A. Finn, Paul A. BedrosianSimultaneous observations of geoelectric and geomagnetic fields produced by magnetospheric ULF waves
Geomagnetic perturbations (BGEO) related to magnetospheric ultralow frequency (ULF) waves induce electric fields within the conductive Earth—geoelectric fields (EGEO)—that in turn drive geomagnetically induced currents. Though numerous past studies have examined ULF wave BGEO from a space weather perspective, few studies have linked ULF waves with EGEO. Using recently available magnetotelluric impAuthorsM. D. Hartinger, X. R. Shih, G. Lucas, Benjamin Scott Murphy, Anna Kelbert, J.B.H. Baker, E. Joshua Rigler, Paul A. BedrosianQuantifying model structural uncertainty using airborne electromagnetic data
The ability to quantify structural uncertainty in geological models that incorporate geophysical data is affected by two primary sources of uncertainty: geophysical parameter uncertainty and uncertainty in the relationship between geophysical parameters and geological properties of interest. Here, we introduce an open-source, trans-dimensional Bayesian Markov chain Monte Carlo (McMC) algorithm GeoAuthorsBurke J. Minsley, N. Leon Foks, Paul A. BedrosianHigh-resolution mapping of the freshwater-brine interface using deterministic and Bayesian inversion of airborne electromagnetic data at Paradox Valley, USA
Salt loads in the Colorado River Basin are a primary water quality concern. Natural groundwater brine discharge to the Dolores River where it passes through the collapsed salt anticline of the Paradox Valley in western Colorado is a significant source of salt to the Colorado River. An airborne electromagnetic survey of Paradox Valley has provided insights into the 3D distribution of brine in theAuthorsLyndsay B. Ball, Paul A. Bedrosian, Burke J. MinsleyA 100-year geoelectric hazard analysis for the U.S. high-voltage power grid
A once-per-century geoelectric hazard map is created for the United States high-voltage power grid. A statistical extrapolation from 31 years of magnetic field measurements is made by identifying 84 geomagnetic storms with the Kp and Dst indices. Data from 24 geomagnetic observatories, 1079 magnetotelluric survey sites, and 17,258 transmission lines are utilized to perform a geoelectric hazardAuthorsGreg M. Lucas, Jeffrey J. Love, Anna Kelbert, Paul A. Bedrosian, E. Joshua RiglerEmpirical estimation of natural geoelectric hazards
Geoelectric field time series can be estimated by convolving estimates of Earth‐surface impedance, such as those obtained from magnetotelluric survey measurements, with historical records of geomagnetic variation obtained at magnetic observatories. This straightforward procedure permits the mapping of geoelectric field variation during magnetic storms. Statistical analysis of the time series allowAuthorsJeffrey J. Love, Paul A. Bedrosian, Anna Kelbert, Greg M. LucasThe first 3D conductivity model of the contiguous US: Reflections on geologic structure and application to induction hazards
Estimation of ground level geoelectric fields has been identified by the National Space Weather Action Plan as a key component of assessment and mitigation of space weather impacts on critical infrastructure. Estimates of spatially and temporally variable electric fields are used to generate statistically based hazard maps and show promise toward monitoring and responding to geomagnetic disturbancAuthorsAnna Kelbert, Paul A. Bedrosian, Benjamin S. MurphyCrustal magmatism and anisotropy beneath the Arabian Shield - A cautionary tale
Volcanism in Saudi Arabia includes a historic eruption close to the holy city of Al Madinah. As part of a volcanic hazard assessment of this area, magnetotelluric (MT) data were collected to investigate the structural setting, the distribution of melt within the crust, and the mantle source of volcanism. Interpretation of a new 3‐D resistivity model includes a shallow graben beneath thin lava fielAuthorsPaul A. Bedrosian, Jared R. Peacock, Maher K. Al-Dhahry, Adel Shareef, D. W. Feucht, Hani M. ZahranLithospheric signature of late Cenozoic extension in electrical resistivity structure of the Rio Grande rift, New Mexico, USA
We present electrical resistivity models of the crust and upper mantle from two‐dimensional (2‐D) inversion of magnetotelluric (MT) data collected in the Rio Grande rift, New Mexico, USA. Previous geophysical studies of the lithosphere beneath the rift identified a low‐velocity zone several hundred kilometers wide, suggesting that the upper mantle is characterized by a very broad zone of modifiedAuthorsD. W. Feucht, Paul A. Bedrosian, Anne F SheehanExtreme‐value geoelectric amplitude and polarization across the northeast United States
Maps are presented of extreme‐value geoelectric field amplitude and horizontal polarization for the Northeast United States. These maps are derived from geoelectric time series calculated for sites across the Northeast by frequency‐domain multiplication (time‐domain convolution) of 172 magnetotelluric impedance tensors, acquired during a survey, with decades‐long, 1‐min resolution time series of gAuthorsJeffrey J. Love, Greg M. Lucas, Paul A. Bedrosian, Anna KelbertNon-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.
- News
*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