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Tom Parsons

I conduct research aimed at improving our ability to forecast hazardous events like earthquakes and tsunamis. Specifically, I study how earthquakes trigger others, how crustal movements cause earthquake stresses, and how to convert geologic observations of earthquake and tsunami processes into quantitative forecasts of use to planners, insurers, and builders.

Professional Experience

  • 1994-Present: Research Geophysicist, U. S. Geological Survey, Menlo Park, CA

  • 1992-1994: National Research Council Postdoctoral Fellow

Education and Certifications

  • 1992 – Ph.D. in Geophysics, Stanford University

  • 1990 – M.S. in Geophysics, Stanford University

  • 1988 – B.S. in Applied Geophysics, UCLA

Affiliations and Memberships*

  • Editor, AGU Advances, 2019-present

  • Editor in Chief, Journal of Geophysical Research, Solid Earth, 2009-2015

  • Editor in Chief, Tectonophysics, 2007-2009

  • Editorial Board, Tectonophysics, 2005-2007

  • Editorial Board, Geology, 1995-2000, 2005-2008

  • Member: Executive Committee, Working Group on California Earthquake Probabilities 2005-present

  • Member: SCEC Planning Committee, 2007-2009

Honors and Awards

  • Senior Scientist (ST): 1/15

  • Fellow American Geophysical Union, Elected 1/12

  • Fulbright Mutual Educational Exchange Grant USA-Greece: 2007-2008

  • Alumni Pillar of Achievement: Golden West College Outstanding Alumni Award (10/07)

  • Fellow Geological Society of America, Elected 10/97

  • Shoemaker Communication Award (10/00)

  • National Association of Government Communicators Gold Screen Award (12/00)

  • National Research Council Post-Doctoral Fellow (8/92)

Science and Products

Filter Total Items: 116

Tectonic implications of post-30 Ma Pacific and North American relative plate motions

The Pacific plate moved northwest relative to North America since 42 Ma. The rapid half rate of Pacific-Farallon spreading allowed the ridge to approach the continent at about 29 Ma. Extinct spreading ridges that occur offshore along 65% of the margin (Lonsdale, 1991) document that fragments of the subducted Farallon slab became captured by the Pacific plate and assumed its motion prior to the act
Authors
R. G. Bohannon, T. Parsons

The active southwest margin of the Colorado Plateau: Uplift of mantle origin

During Cenozoic time, the Colorado Plateau was raised about 2 km above sea level. The most-recent and best-documented uplift of the plateau (∼1 km) has been concentrated at its southwest margin between 6 and 1 Ma, whereas the eastern Colorado Plateau may have been at high elevations since Eocene time. To better understand the recent tectonic activity at the southwest margin of the Colorado Plateau
Authors
T. Parsons, J. McCarthy

The Basin and Range province

No abstract available.
Authors
Thomas E. Parsons
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program

Mantle plume influence on the Neogene uplift and extension of the US western Cordillera?

espite its highly extended and thinned crust, much of the western Cordillera in the United States is elevated more than 1 km above sea level. Therefore, this region cannot be thought of as thick crust floating isostatically in a uniform mantle; rather, the lithospheric mantle and/or the upper asthenosphere must vary in thickness or density across the region. Utilizing crustal thickness and density
Authors
T. Parsons, G. A. Thompson, Norman H. Sleep

Insights into the kinematic Cenozoic evolution of the Basin and Range-Colorado Plateau transition from coincident seismic refraction and reflection data

Estimates of surface extension in the southern Basin and Range province and transition into the Colorado Plateau range from a few percent to several hundred percent locally, yet the crustal thickness varies perhaps only 10-15 km across these provinces. Within the southern Basin and Range and the metamorphic core complex belt, extremely extended crust is directly juxtaposed against equally thick (o
Authors
J. McCarthy, T. Parsons

Does magmatism influence low-angle normal faulting?: Comment and reply

No abstract available.
Authors
An Yin, Tom Parsons, George A. Thompson

Does magmatism influence low-angle normal faulting?

Synextensional magmatism has long been recognized as a ubiquitous characteristic of highly extended terranes in the western Cordillera of the United States. Intrusive magmatism can have severe effects on the local stress field of the rocks intruded. Because a lower angle fault undergoes increased normal stress from the weight of the upper plate, it becomes more difficult for such a fault to slide.
Authors
Thomas E. Parsons, George A. Thompson

Seismic constraints on the nature of lower crustal reflectors beneath the extending Southern Transition Zone of the Colorado Plateau, Arizona

We determine the reflection polarity and exploit variations in P and S wave reflectivity and P wave amplitude versus offset (AVO) to constrain the origin of lower crustal reflectivity observed on new three-component seismic data recorded across the structural transition of the Colorado Plateau. The near vertical incidence reflection data were collected by Stanford University in 1989 as part of the
Authors
Thomas E. Parsons, John M. Howie, George A. Thompson

Non-USGS Publications**

1992, by Parsons, T. et al., Department of Geophysics, Stanford University
1992, by Parsons, T., et al., Department of Geophysics, Stanford University
1991, by Howie, J.M., et al., Department of Geophysics, Stanford University
1991, by Parsons, T., and Thompson, G.A., Department of Geophysics, Stanford University

**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.

No Result Found
No results found.

Science and Products

Filter Total Items: 116

Tectonic implications of post-30 Ma Pacific and North American relative plate motions

The Pacific plate moved northwest relative to North America since 42 Ma. The rapid half rate of Pacific-Farallon spreading allowed the ridge to approach the continent at about 29 Ma. Extinct spreading ridges that occur offshore along 65% of the margin (Lonsdale, 1991) document that fragments of the subducted Farallon slab became captured by the Pacific plate and assumed its motion prior to the act
Authors
R. G. Bohannon, T. Parsons

The active southwest margin of the Colorado Plateau: Uplift of mantle origin

During Cenozoic time, the Colorado Plateau was raised about 2 km above sea level. The most-recent and best-documented uplift of the plateau (∼1 km) has been concentrated at its southwest margin between 6 and 1 Ma, whereas the eastern Colorado Plateau may have been at high elevations since Eocene time. To better understand the recent tectonic activity at the southwest margin of the Colorado Plateau
Authors
T. Parsons, J. McCarthy

The Basin and Range province

No abstract available.
Authors
Thomas E. Parsons
By
Natural Hazards Mission Area, Coastal and Marine Hazards and Resources Program

Mantle plume influence on the Neogene uplift and extension of the US western Cordillera?

espite its highly extended and thinned crust, much of the western Cordillera in the United States is elevated more than 1 km above sea level. Therefore, this region cannot be thought of as thick crust floating isostatically in a uniform mantle; rather, the lithospheric mantle and/or the upper asthenosphere must vary in thickness or density across the region. Utilizing crustal thickness and density
Authors
T. Parsons, G. A. Thompson, Norman H. Sleep

Insights into the kinematic Cenozoic evolution of the Basin and Range-Colorado Plateau transition from coincident seismic refraction and reflection data

Estimates of surface extension in the southern Basin and Range province and transition into the Colorado Plateau range from a few percent to several hundred percent locally, yet the crustal thickness varies perhaps only 10-15 km across these provinces. Within the southern Basin and Range and the metamorphic core complex belt, extremely extended crust is directly juxtaposed against equally thick (o
Authors
J. McCarthy, T. Parsons

Does magmatism influence low-angle normal faulting?: Comment and reply

No abstract available.
Authors
An Yin, Tom Parsons, George A. Thompson

Does magmatism influence low-angle normal faulting?

Synextensional magmatism has long been recognized as a ubiquitous characteristic of highly extended terranes in the western Cordillera of the United States. Intrusive magmatism can have severe effects on the local stress field of the rocks intruded. Because a lower angle fault undergoes increased normal stress from the weight of the upper plate, it becomes more difficult for such a fault to slide.
Authors
Thomas E. Parsons, George A. Thompson

Seismic constraints on the nature of lower crustal reflectors beneath the extending Southern Transition Zone of the Colorado Plateau, Arizona

We determine the reflection polarity and exploit variations in P and S wave reflectivity and P wave amplitude versus offset (AVO) to constrain the origin of lower crustal reflectivity observed on new three-component seismic data recorded across the structural transition of the Colorado Plateau. The near vertical incidence reflection data were collected by Stanford University in 1989 as part of the
Authors
Thomas E. Parsons, John M. Howie, George A. Thompson

Non-USGS Publications**

1992, by Parsons, T. et al., Department of Geophysics, Stanford University
1992, by Parsons, T., et al., Department of Geophysics, Stanford University
1991, by Howie, J.M., et al., Department of Geophysics, Stanford University
1991, by Parsons, T., and Thompson, G.A., Department of Geophysics, Stanford University

**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.

No Result Found
No results found.

*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

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