Dr. Charles Cashman Trexler
Mendenhall Research Fellow
Earthquake Science Center
United States Geological Survey
Professional Preparation:
Ph.D., University of California, Davis, Geology, 2018
B.A. with honors, Whitman College, Geology, 2011
Exploring Academic Careers at Liberal Arts Colleges and Universities workshop, 2018
Preparing for an Academic Career in the Geosciences Workshop, summer 2016
Earth Educator Rendezvous 2016, Madison, WI
B.A. with honors, Whitman College, Geology, 2011
Exploring Academic Careers at Liberal Arts Colleges and Universities workshop, 2018
Preparing for an Academic Career in the Geosciences Workshop, summer 2016
Earth Educator Rendezvous 2016, Madison, WI
Appointments
2020-present Mendenhall Research Fellow, United States Geological Survey Earthquake Science Center
2018-2020 Visiting Assistant Professor, Dept. of Geology & Geography, Ohio Wesleyan University
2015-2018 lecturer, Dept. of Earth & Planetary Sciences, UC Davis
2015-2016 department seminar coordinator, Dept. of Earth & Planetary Sciences, UC Davis
2015-2016 graduate student representative to the faculty, Dept. of Earth & Planetary Sciences, UC Davis
2012-2018 Teaching assistant, University of California, Davis (introductory geology; structural geology; geomorphology; field
methods; field camp)
2012-2018 Graduate Student, University of California, Davis (advanced to PhD candidacy May 2014)
2012 GeoCorps America Geologist-In-Park, Mount Rainier National Park (Geological Society of America/National Park
Service)
2011 Interpretive Ranger (intern), Canyonlands National Park (Student Conservation Association)
2010 Student researcher, EarthScope Bighorn Mountains Seismic Experiment and Keck Geology Consortium Bighorn
Mountains project
2009 Intern, United States Geological Survey, Denver
2018-2020 Visiting Assistant Professor, Dept. of Geology & Geography, Ohio Wesleyan University
2015-2018 lecturer, Dept. of Earth & Planetary Sciences, UC Davis
2015-2016 department seminar coordinator, Dept. of Earth & Planetary Sciences, UC Davis
2015-2016 graduate student representative to the faculty, Dept. of Earth & Planetary Sciences, UC Davis
2012-2018 Teaching assistant, University of California, Davis (introductory geology; structural geology; geomorphology; field
methods; field camp)
2012-2018 Graduate Student, University of California, Davis (advanced to PhD candidacy May 2014)
2012 GeoCorps America Geologist-In-Park, Mount Rainier National Park (Geological Society of America/National Park
Service)
2011 Interpretive Ranger (intern), Canyonlands National Park (Student Conservation Association)
2010 Student researcher, EarthScope Bighorn Mountains Seismic Experiment and Keck Geology Consortium Bighorn
Mountains project
2009 Intern, United States Geological Survey, Denver
Honors & Awards
2014 - National Science Foundation Graduate Research Fellowship, Hon. Mention
2013 - Achievement Reward for College Scientists, UC Davis
2011 - Leeds Prize in Geology, Whitman College
2010- Keck Geology Consortium Bighorn Mountains Project member
2013 - Achievement Reward for College Scientists, UC Davis
2011 - Leeds Prize in Geology, Whitman College
2010- Keck Geology Consortium Bighorn Mountains Project member
Grants
2015 - NSF EAR Tectonics Grant 1524631 (contributor; PI: Eric Cowgill)
2015 - Evolving Earth fellowship
2015 - American Association of Petroleum Geologists Grant-In-Aid
2014 - Geological Society of America Graduate Student Research Grant
2013 - Geological Society of America Graduate Student Research Grant
2015 - Evolving Earth fellowship
2015 - American Association of Petroleum Geologists Grant-In-Aid
2014 - Geological Society of America Graduate Student Research Grant
2013 - Geological Society of America Graduate Student Research Grant
Invited Lectures, Talks, & Field Trips
2020 Earthquake Science Center, United States Geological Survey [June 10]
2019 University of Nevada, Reno [October 7]
2019 University of Cincinnati [March 8]
2019 Denison University [March 5]
2018 Geology Colloquium, Humboldt State University [March 5]
2016 John & Mary Louise Riley Geology Lecture Series, Sonoma State University (Oct. 20, 2016)
2016 Active Tectonics in Napa Valley (field trip), Geological Society of America Structure & Tectonics Forum
(with A. Morelan) July 31, 2016)
2019 University of Nevada, Reno [October 7]
2019 University of Cincinnati [March 8]
2019 Denison University [March 5]
2018 Geology Colloquium, Humboldt State University [March 5]
2016 John & Mary Louise Riley Geology Lecture Series, Sonoma State University (Oct. 20, 2016)
2016 Active Tectonics in Napa Valley (field trip), Geological Society of America Structure & Tectonics Forum
(with A. Morelan) July 31, 2016)
Publications
Trexler, C.C., Philibosian, B., and Willard, J.G. (in press, Tektonika) Geometry and Quaternary activity of faults and folds within the Sacramento/San Joaquin Delta, northern California.
Trexler, C.C., Cowgill, E.S., Niemi, N.A., and Vasey, D.A., 2023. Basin closure and growth of a continental collision zone: Insights from balanced cross sections and low-temperature thermochronology in the Georgian Greater Caucasus, Tektonika, v.1 n.2 p. 198-208. https://doi.org/10.55575/tektonika2023.1.2.50
Vasey, D.A., Garcia, L., Cowgill, E., Trexler, C.C., and Godoladze, T. 2023. Episodic evolution of a protracted convergent margin revealed by detrital zircon geochronology in the Greater Caucasus, Basin Research, https://doi.org/10.1111/bre.12825
Trexler, C.C. Morelan, A.E., Catchings, R., Goldman, M., and Willard, J., 2022. Evidence of Active Quaternary Deformation on the Great Valley Fault System near Winters, Northern California, The Seismic Record, v. 2 n. 4, p. 248-259. doi:10.1785/0320220029
Trexler, C.C., Cowgill, E.S., Niemi, N.A., Vasey, D.A., and Godoladze, T., 2022. Tectonostratigraphy and major structures of the Georgian Greater Caucasus: Implications for structural architecture, along-strike continuity, and orogen evolution, Geosphere. https://doi.org/10.1130/GES02385.1
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., and Godoladze, T., 2020. Rate of active shortening across the southern thrust front of the Greater Caucasus in western Georgia from kinematic modeling of folded river terraces above a listric thrust. Earth and Planetary Science Letters, v. 544, doi: 10.1016/j.epsl.2020.116362
Trexler, C.C., Morelan, A.E., Oskin, M.E., and Kreylos, O., 2018. Surface Slip from the 2014 South Napa earthquake measured with structure-from- motion and 3D virtual reality. Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL078012
Cowgill, E., Forte, A.M., Niemi, N, Avdeev, B., Tye, A., Trexler, C.C., Javakhishvili, Z., Elashvili, M., and Godoladze, T., 2016. Relict basin closure and crustal shortening budgets during continental collision: An example from Caucasus sediment provenance, Tectonics, 2918– 2947, doi:10.1002/2016TC004295.
Morelan, A.E., Trexler, C.C., and Oskin, M.E., 2015. Surface-Rupture and Slip Observations on the Day of the 24 August 2014 South Napa Earthquake. Seismological Research Letters, v.86, no. 4, p. 1119-1127.
Mumladze, T., Forte, A. M., Cowgill, E. S., Trexler, C. C., Niemi, N. A., Burak Yıkılmaz, M., and Kellogg, L. H., 2015, Subducted, detached, and torn slabs beneath the Greater Caucasus: GeoResJ, v. 5, no. 0, p. 36-46.
Trexler, C.C., Morelan, A.E., and Oskin, M.E., 2014, Rapid Mapping of Surface Rupture from the South Napa Earthquake. Abstract S31G-01 presented at 2014 AGU Fall Meeting: San Francisco, Calif. 15 December 2014.
Trexler, C.C., Cowgill, E., Forte, A.M., Mumladze, T., Sokhadze, G., Elashvili, M., and Niemi, N.A., 2013, Inheritance of earthquake hazard from suturing: the Himalayas as an analogue for the structural architecture and seismic potential of the Greater Caucasus. Abstract T11A-2423 presented at 2013 AGU Fall Meeting: San Francisco, Calif. 3-7 December 2013.
Trexler, C. 2011. Topographic Lineaments and Expression of Fracture Arrays in the Edelman and North Paint Rock Creek Lineaments, Bighorn Mountains, Wyoming. Keck Geology Consortium Symposium Volume, 2011.
M. Chamberlin, E. Dalley, T. Doane, B. McAtee, D. Oakley, C. Trexler, B.Young, E. Erslev, and C. Siddoway, 2011. Brittle fracture studies in post-Permian strata of the western hlank and in the crystalline core of the Bighorn Mountains arch, Wyoming: A component of the NSF EarthScope Bighorns Project. NSF Earthscope Project Annual Meeting Abstract 2011
M. Hudson, K. Turner, and C. Trexler, 2009. Regional joint analysis for the Buffalo National River area of northern Arkansas: Implications or tectonic history and landscape inhluence. Geological Society of America Annual Meeting Abstracts 2009.
Trexler, C.C., Cowgill, E.S., Niemi, N.A., and Vasey, D.A., 2023. Basin closure and growth of a continental collision zone: Insights from balanced cross sections and low-temperature thermochronology in the Georgian Greater Caucasus, Tektonika, v.1 n.2 p. 198-208. https://doi.org/10.55575/tektonika2023.1.2.50
Vasey, D.A., Garcia, L., Cowgill, E., Trexler, C.C., and Godoladze, T. 2023. Episodic evolution of a protracted convergent margin revealed by detrital zircon geochronology in the Greater Caucasus, Basin Research, https://doi.org/10.1111/bre.12825
Trexler, C.C. Morelan, A.E., Catchings, R., Goldman, M., and Willard, J., 2022. Evidence of Active Quaternary Deformation on the Great Valley Fault System near Winters, Northern California, The Seismic Record, v. 2 n. 4, p. 248-259. doi:10.1785/0320220029
Trexler, C.C., Cowgill, E.S., Niemi, N.A., Vasey, D.A., and Godoladze, T., 2022. Tectonostratigraphy and major structures of the Georgian Greater Caucasus: Implications for structural architecture, along-strike continuity, and orogen evolution, Geosphere. https://doi.org/10.1130/GES02385.1
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., and Godoladze, T., 2020. Rate of active shortening across the southern thrust front of the Greater Caucasus in western Georgia from kinematic modeling of folded river terraces above a listric thrust. Earth and Planetary Science Letters, v. 544, doi: 10.1016/j.epsl.2020.116362
Trexler, C.C., Morelan, A.E., Oskin, M.E., and Kreylos, O., 2018. Surface Slip from the 2014 South Napa earthquake measured with structure-from- motion and 3D virtual reality. Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL078012
Cowgill, E., Forte, A.M., Niemi, N, Avdeev, B., Tye, A., Trexler, C.C., Javakhishvili, Z., Elashvili, M., and Godoladze, T., 2016. Relict basin closure and crustal shortening budgets during continental collision: An example from Caucasus sediment provenance, Tectonics, 2918– 2947, doi:10.1002/2016TC004295.
Morelan, A.E., Trexler, C.C., and Oskin, M.E., 2015. Surface-Rupture and Slip Observations on the Day of the 24 August 2014 South Napa Earthquake. Seismological Research Letters, v.86, no. 4, p. 1119-1127.
Mumladze, T., Forte, A. M., Cowgill, E. S., Trexler, C. C., Niemi, N. A., Burak Yıkılmaz, M., and Kellogg, L. H., 2015, Subducted, detached, and torn slabs beneath the Greater Caucasus: GeoResJ, v. 5, no. 0, p. 36-46.
Trexler, C.C., Morelan, A.E., and Oskin, M.E., 2014, Rapid Mapping of Surface Rupture from the South Napa Earthquake. Abstract S31G-01 presented at 2014 AGU Fall Meeting: San Francisco, Calif. 15 December 2014.
Trexler, C.C., Cowgill, E., Forte, A.M., Mumladze, T., Sokhadze, G., Elashvili, M., and Niemi, N.A., 2013, Inheritance of earthquake hazard from suturing: the Himalayas as an analogue for the structural architecture and seismic potential of the Greater Caucasus. Abstract T11A-2423 presented at 2013 AGU Fall Meeting: San Francisco, Calif. 3-7 December 2013.
Trexler, C. 2011. Topographic Lineaments and Expression of Fracture Arrays in the Edelman and North Paint Rock Creek Lineaments, Bighorn Mountains, Wyoming. Keck Geology Consortium Symposium Volume, 2011.
M. Chamberlin, E. Dalley, T. Doane, B. McAtee, D. Oakley, C. Trexler, B.Young, E. Erslev, and C. Siddoway, 2011. Brittle fracture studies in post-Permian strata of the western hlank and in the crystalline core of the Bighorn Mountains arch, Wyoming: A component of the NSF EarthScope Bighorns Project. NSF Earthscope Project Annual Meeting Abstract 2011
M. Hudson, K. Turner, and C. Trexler, 2009. Regional joint analysis for the Buffalo National River area of northern Arkansas: Implications or tectonic history and landscape inhluence. Geological Society of America Annual Meeting Abstracts 2009.
Presentations
Trexler, C.C., Vermeer, J., Hammer, M., Doyle, M., and Williams, T. 2023. Shallow sediment cores provide constraints on late Quaternary displacement in the Pittsburg - Kirby Hills Fault Zone, Solano County, northern California, presented at the American Geophysical Union annual meeting, 12 December 2023.
Trexler, C.C., Vermeer, J., Hecker, S., Elliott, A., and Hammer, M. 2023. Three-dimensional visualization and implications for reconstruction of the Chalk Hill paleoseismic site on the Rodgers creek fault near Windsor, California, presented at the Seismological Society of America meeting, 20 April 2023.
Trexler, C.C., Philibosian, B., Willard, J., Sickler, R.R., and Mahan, S.A. 2022. Investigating slow-moving, complex faults with a combination of geomorphology, bedrock, and subsurface datasets: an example from the Sacramento - San Joaquin Delta, northern California, presented at Geological Society of America Annual Meeting, 11 October 2022.
Trexler, C.C. and Willard, J. 2022. Active deformation and the role of inherited structures in the Sacramento - San Joaquin Delta, northern California, constrained using a compilation of geomorphic, geologic, and geodetic datasets, presented at Geological Society of America Joint Cordilleran/Rocky Mountain Section Meeting, 16 March 2022.
Trexler, C. C., Kelsey, H. M., and Furlong, K. P. 2021. Active deformation along multiple strands of the northern Maacama fault, Mendocino County, California, from lidar-derived topographic data, presented at Geological Society of America Annual Meeting, 10 October 2021.
Trexler, C. C., Morelan, A. E., DeLong, S. B., Catchings, R. D., Sickler, R. R., Chan, J. H. and Goldman, M. R. 2021. Topographic expression of active faulting along the Great Valley Thrust System near Winters, Northern California, presented at Geological Society of America Annual Meeting, 11 October 2021.
Trexler, C.,C., Morelan, A. E., DeLong, S., & Pickering, A. J. 2021. Topographic expression of active faulting along the Great Valley Thrust system near Winters, northern California, presented at 2021 SCEC Annual Meeting, 12-17 September 2021.
Trexler, C.C. 2020. Topographic expression of active faulting and folding in the Sacramento/San Joaquin Delta, California. Abstract 144-17, presented at the Geological Society of America Annual Meeting, 28 October 2020.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q.G., and Godoladze, T. 2019. Determining shortening rates by integrated structural modeling of deformed fluvial terraces and underlying folded strata: an example from the western Greater Caucasus. Abstract T13-280, presented at the Geological Society of America Annual Meeting: Phoenix, AZ. 23 September 2019.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2018. Balanced cross sections record marin basin closure and growth of a continental collision zone: Greater Caucasus Mountains, Republic of Georgia. Abstract T177-375, presented at the Geological Society of America Annual Meeting: Indianapolis, IN. 4 November 2018.
Trexler, C.C., Cowgill, E.S., Forte, A.M., Niemi, N.A., and Godoladze, T., 2018. Structural investigations of the tectonic history ofthe western Greater Caucasus: exploring the geological expression of the transition from subduction to slab breakoff. EGU2018-11592 presented at the 2018 European Geosciences Union: Vienna, Austria, 12 April 2018.
Trexler, C.C., Cowgill, E.S., Forte, A.M., Niemi, N.A., and Godoladze, T., 2018. Basin closure and growth of a continental collision zone: insights from structural data and balanced cross sections, Georgian Greater Caucasus. EGU2018-11754, presented at the 2018 European Geosciences Union: Vienna, Austria, 12 April 2018.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., Godoladze, T., and Gogoladze, S., 2017. Active shortening and the geological expression of the transition from subduction to continental collision in the western Greater Caucasus, Republic of Georgia. Abstract T51H-03, presented at the 2017 American Geophysical Union Fall Meeting: New Orleans, LA. 15 December 2017.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., Godoladze, T., and Gogoladze, S., 2017. Deformed river terraces show active shortening in the western Greater Caucasus, Republic of Georgia. Abstract 345-13, Session T233 presented at the 2017 Geological Society of America Annual Meeting: Seattle, Wash. 25 October 2017.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2016. Exploring the geological expression of the transition from subduction to continental collision in the Georgian Greater Caucasus. Abstract T53B-01 presented at the 2016 AGU Fall Meeting: San Francisco, Calif. 16 December 2016.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2015. Exploring Subduction, slab breakoff, and upper-plate shortening in the Georgian Greater Caucasus: shortening estimates from area- and line-balanced crustal scale cross sections. Abstract T31B-2886 presented at 2015 AGU Fall Meeting: San Francisco, Calif. 16 December 2015.
Trexler, C.C., Morelan, A.E., and Oskin, M.E., 2014, Rapid Mapping of Surface Rupture from the South Napa Earthquake. Abstract S31G-01 presented at 2014 AGU Fall Meeting: San Francisco, Calif. 15 December 2014.
Trexler, C.C., Cowgill, E., Forte, A.M., Mumladze, T., Sokhadze, G., Elashvili, M., and Niemi, N.A., 2013, Inheritance of earthquake hazard from suturing: the Himalayas as an analogue for the structural architecture and seismic potential of the Greater Caucasus. Abstract T11A-2423 presented at 2013 AGU Fall Meeting: San Francisco, Calif. 3-7 December 2013.
Trexler, C.C., Vermeer, J., Hecker, S., Elliott, A., and Hammer, M. 2023. Three-dimensional visualization and implications for reconstruction of the Chalk Hill paleoseismic site on the Rodgers creek fault near Windsor, California, presented at the Seismological Society of America meeting, 20 April 2023.
Trexler, C.C., Philibosian, B., Willard, J., Sickler, R.R., and Mahan, S.A. 2022. Investigating slow-moving, complex faults with a combination of geomorphology, bedrock, and subsurface datasets: an example from the Sacramento - San Joaquin Delta, northern California, presented at Geological Society of America Annual Meeting, 11 October 2022.
Trexler, C.C. and Willard, J. 2022. Active deformation and the role of inherited structures in the Sacramento - San Joaquin Delta, northern California, constrained using a compilation of geomorphic, geologic, and geodetic datasets, presented at Geological Society of America Joint Cordilleran/Rocky Mountain Section Meeting, 16 March 2022.
Trexler, C. C., Kelsey, H. M., and Furlong, K. P. 2021. Active deformation along multiple strands of the northern Maacama fault, Mendocino County, California, from lidar-derived topographic data, presented at Geological Society of America Annual Meeting, 10 October 2021.
Trexler, C. C., Morelan, A. E., DeLong, S. B., Catchings, R. D., Sickler, R. R., Chan, J. H. and Goldman, M. R. 2021. Topographic expression of active faulting along the Great Valley Thrust System near Winters, Northern California, presented at Geological Society of America Annual Meeting, 11 October 2021.
Trexler, C.,C., Morelan, A. E., DeLong, S., & Pickering, A. J. 2021. Topographic expression of active faulting along the Great Valley Thrust system near Winters, northern California, presented at 2021 SCEC Annual Meeting, 12-17 September 2021.
Trexler, C.C. 2020. Topographic expression of active faulting and folding in the Sacramento/San Joaquin Delta, California. Abstract 144-17, presented at the Geological Society of America Annual Meeting, 28 October 2020.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q.G., and Godoladze, T. 2019. Determining shortening rates by integrated structural modeling of deformed fluvial terraces and underlying folded strata: an example from the western Greater Caucasus. Abstract T13-280, presented at the Geological Society of America Annual Meeting: Phoenix, AZ. 23 September 2019.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2018. Balanced cross sections record marin basin closure and growth of a continental collision zone: Greater Caucasus Mountains, Republic of Georgia. Abstract T177-375, presented at the Geological Society of America Annual Meeting: Indianapolis, IN. 4 November 2018.
Trexler, C.C., Cowgill, E.S., Forte, A.M., Niemi, N.A., and Godoladze, T., 2018. Structural investigations of the tectonic history ofthe western Greater Caucasus: exploring the geological expression of the transition from subduction to slab breakoff. EGU2018-11592 presented at the 2018 European Geosciences Union: Vienna, Austria, 12 April 2018.
Trexler, C.C., Cowgill, E.S., Forte, A.M., Niemi, N.A., and Godoladze, T., 2018. Basin closure and growth of a continental collision zone: insights from structural data and balanced cross sections, Georgian Greater Caucasus. EGU2018-11754, presented at the 2018 European Geosciences Union: Vienna, Austria, 12 April 2018.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., Godoladze, T., and Gogoladze, S., 2017. Active shortening and the geological expression of the transition from subduction to continental collision in the western Greater Caucasus, Republic of Georgia. Abstract T51H-03, presented at the 2017 American Geophysical Union Fall Meeting: New Orleans, LA. 15 December 2017.
Trexler, C.C., Cowgill, E.S., Spencer, J.Q., Godoladze, T., and Gogoladze, S., 2017. Deformed river terraces show active shortening in the western Greater Caucasus, Republic of Georgia. Abstract 345-13, Session T233 presented at the 2017 Geological Society of America Annual Meeting: Seattle, Wash. 25 October 2017.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2016. Exploring the geological expression of the transition from subduction to continental collision in the Georgian Greater Caucasus. Abstract T53B-01 presented at the 2016 AGU Fall Meeting: San Francisco, Calif. 16 December 2016.
Trexler, C.C., Cowgill, E.S., and Niemi, N.A., 2015. Exploring Subduction, slab breakoff, and upper-plate shortening in the Georgian Greater Caucasus: shortening estimates from area- and line-balanced crustal scale cross sections. Abstract T31B-2886 presented at 2015 AGU Fall Meeting: San Francisco, Calif. 16 December 2015.
Trexler, C.C., Morelan, A.E., and Oskin, M.E., 2014, Rapid Mapping of Surface Rupture from the South Napa Earthquake. Abstract S31G-01 presented at 2014 AGU Fall Meeting: San Francisco, Calif. 15 December 2014.
Trexler, C.C., Cowgill, E., Forte, A.M., Mumladze, T., Sokhadze, G., Elashvili, M., and Niemi, N.A., 2013, Inheritance of earthquake hazard from suturing: the Himalayas as an analogue for the structural architecture and seismic potential of the Greater Caucasus. Abstract T11A-2423 presented at 2013 AGU Fall Meeting: San Francisco, Calif. 3-7 December 2013.