University of Nevada Reno, NV, Ph.D. 2009
Humboldt State University, Humboldt, CA: M.S., Environmental Systems (Geology), 1997
University of California, Santa Cruz, CA: B.A., Earth Science, 1992
Commission member, Alaska Seismic Hazards Safety Commission (2010)
Humboldt State University, Adjunct Faculty, 2009-date
State of Alaska, Dept. of Geological and Geophysical Surveys, Earthquake Geologist 2009-
Center for Neotectonic Studies, University of Nevada, Reno, Research Assistant, 2004-9
William Lettis & Associates, Inc., Walnut Creek, CA, Project Geologist, 1999-2004
US Geological Survey, project paleoseismologist, 10 trenches, Puget Sound, Wa, 1998-2003
My primary research focus areas are Quaternary geology, paleoseismology, and geomorphology. I use a multidisciplinary approach to evaluate regional neotectonics, as well as the paleoseismic history of individual active faults. The ultimate goal of my work is to develop an understanding of how the surface of the earth evolves and application of this knowledge to seismic hazard analyses. I have conducted paleoseismic studies funded by the U.S. Geological Survey and NSF throughout the western U.S. including faults in California, New Mexico, Washington, Alaska, and Nevada. My international experience includes projects in Turkey, Taiwan, Guatemala, Jamaica, and Haiti.
My work has contributed to geologic hazard assessments for large infrastructure projects including: (1) trenching potential dam sites in the northern Sacramento Valley, California for the California Department of Water Resources; (2) geotechnical site characterization for Pacific Gas and Electric Company’s Diablo Canyon Nuclear Power Plant, San Luis Obispo, California; (3) seismic source model compilation for Entergy Potomac’s Grand Gulf nuclear power plant expansion in Mississippi; (4) trenching to validate fault crossing design for faults along the Baku-Tbilisi-Ceyhan (BTC) crude oil pipeline, Turkey and (5) geologic studies in support of proposed natural gas pipelines in Alaska.
Koehler, R.D., and Reger, R.D., (2011), Reconnaissance evaluation of the Lake Clark fault, Tyonek area, Alaska, Preliminary Interpretive Report 2011-1, State of Alaska, Division of Geological and Geophysical Surveys.
Koehler, R.D.,and Mann, P., (2011), Field observations from the 12 January 2010 Haiti earthquake: Implications for seismic hazards and future post-earthquake reconnaissance investigations in Alaska, report of Investigations, State of Alaska, Division of Geological & Geophysical Surveys.
Koehler, R.D., Haeussler, P.J., Personius, S., Schwarz, D., and Seitz, G., (2011), Paleoseismic results from field studies along the central Denali fault, Chistochina Glacier area, south-central Alaska, Report of Investigations, State of Alaska, Division of Geological and Geophysical Surveys.
Prentice, C., Mann, P., Crone, A.J., Gold, R.D., Hudnut, K.W., Briggs, R.W., Koehler, R.D., Jean, P. (2010), Seismic hazard of the Enriquillo-Plantain Garden fault in Haiti inferred from paleoseismology, Nature Geoscience, doi: 10.1038/ngeo991.
Koehler, R.D., 2010,Technical review of a trench across a potential fault scarp feature east of Lower Talarik Creek, Lake Iliamna area, southwestern Alaska, State of Alaska, Division of Geological & Geophysical Surveys, Miscellaneous Publication 139.
DuRoss, C.B., de Polo, C.M., Koehler, R.D., Bowman, S.D., McDonald, G.N., and Shaw, L.M., 2010, Immediate Scientific Response to the 2008 Wells, Nevada, Earthquake, NBMG/USGS 2008 Wells, Nevada Earthquake Report.
Koehler, R.D., and Wesnousky, S,G., (2010), Late Pleistocene regional extension rate derived from earthquake geology of late Quaternary faults across Great Basin, Nevada between 38.50 and 400 N latitude, Geological Society of America Bulletin.
Hanks, T., and Koehler, R.D., 2009, Diffusion-equation representations of landform evolution in the simplest circumstances, In: Bierman and Montgomery, Key Concepts in Geomorphology, online vignettes, http://serc.carleton.edu/vignettes/index.html
Delattre, M.P. and Koehler, R.D., 2009, Geologic map of the Camp Meeker 7.5’ Quadrangle, Sonoma County, California: A digital database, Version 1.0, California Geological Survey Preliminary Geologic Map website: http://www.conservation.ca.gov/CGS/rghm/rgm/preliminary_geologic_maps.htm
Delattre, M.P., and Koehler, R.D., 2008, Geologic Map of the Sebastopol 7.5’ quadrangle, Sonoma
County, California: A digital database: California Geological Survey Preliminary Geologic
Map website: http://www.conservation.ca.gov/CGS/rghm/rgm/preliminary_geologic_maps.htm
Turner, R., Koehler, R.D., Briggs, R.W., and Wesnousky, S.G. (2008), Paleoseismic and slip rate observations along the Honey Lake Fault, northeastern California, Bulletin of the Seismological Society of America, Vo. 98, No. 4.
Kelson, K.I., A.R. Streig, R.D. Koehler, and Keng-Hao Kang, 2006, Timing of Late Holocene Paleoearthquakes on the Northern San Andreas Fault at the Fort Ross Orchard Site, Sonoma County, California, Bulletin of the Seismological Society of America, 96, p. 1012-1028.
Witter, R.C., Knudsen, K.L., Sowers, J.M., Wentworth, C.M., Koehler, R.D., and Randolph C.E. with digital database by Wentworth, C.M, Brooks, S.K., and Gans, K.D., 2006, Maps of Quaternary Deposits and Liquefaction Susceptibility in the Central San Francisco Bay Region, California, U.S. Geological Survey, Open-File Report 2006-1037, Version 1.1.
Johnson, S.Y., A.R. Nelson, S.F. Personius, R.E. Wells, H.M. Kelsey, B.L. Sherrod, K. Okumura, R. Koehler, III, R. Witter, L. Bradley, and D.J. Harding, (2004), Evidence for late Holocene earthquakes on the Utsalady Point fault, northern Puget Lowland, Washington, Bulletin of the Seismological Society of America, V. 94, No. 6.
Nelson, A.R., Johnson S.Y., Kelsey, H.M., Wells, R.E., Sherrod, B.L., Pezzopane, S.K., Bradley, L.A., Koehler, R.D., and Bucknam, R.C., (2003), Late Holocene Earthquakes on the Toe Jam Hill Fault, Seattle Fault Zone, Bainbridge Island, Washinghton, Geological Society of America Bulletin, v. 115, no. 11, p. 1388-1403.
Bezore, S.P.,Koehler, R.D., and Witter, R.C., 2003, Geologic Map of the Two Rock 7.5’ Quadrangle Sonoma County, California: A Digital Database, Version 1.0, California Geological Survey.
Clahan, K.B., Bezore, S.P., Koehler, R.D., and Witter, R.C., 2003, Geologic Map of the Cotati 7.5’ Quadrangle Sonoma County, California: A Digital Database, Version 1.0, California Geological Survey, Digital Database by: Mascorro, M.T and Ford, E.W.
Office: State of Alaska, Geological and Geophysical Surveys (DGGS), 3354 College Road, Fairbanks, Alaska 99709-3707