Katherine (Kate) Scharer, PhD
Dr. Scharer holds a Ph.D. from the University of Oregon and a B.S. in Geological Sciences from the University of Washington.
Prior to coming to the USGS, she was a professor at Appalachian State University in North Carolina. Dr. Scharer studies the timing and size of pre-historic earthquakes along the San Andreas Fault and other active faults in southern California, Alaska, and the Dominican Republic. She also investigates the deformation produced by tectonic motion through a combination of field mapping, lidar analysis, and Quaternary geochronologic methods.
Science and Products
Filter Total Items: 52
Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures
Surface rupture in the 2019 Ridgecrest, California, earthquake sequence occurred along two orthogonal cross faults and includes dominantly left‐lateral and northeast‐striking rupture in the Mw 6.4 foreshock and dominantly right‐lateral and northwest‐striking rupture in the Mw 7.1 mainshock. We present >650 field‐based, surface‐displacement observations for these ruptures and synthesize...
Authors
Christopher B. DuRoss, Ryan D. Gold, Timothy E. Dawson, Katherine M. Scharer, Katherine J. Kendrick, Sinan Akciz, Stephen J. Angster, Jeffery Bachhuber, Steven Bacon, Scott E.K. Bennett, Luke Blair, Benjamin A. Brooks, Thomas Bullard, W. Paul Burgess, Colin Chupik, Michael DeFrisco, Jaime Delano, James D. Dolan, Erik Frost, Nick Graehl, Elizabeth Haddon, Alexandra Elise Hatem, Janis Hernandez, Christopher S. Hitchcock, Kennth Hudnut, Jessica Thompson Jobe, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Christopher Madugo, Devin McPhillips, Christopher Milliner, Alexander Morelan, Brian Olson, Jason Patton, Belle E. Philibosian, Alexandra J. Pickering, Ian Pierce, Daniel J. Ponti, Gordon G. Seitz, Eleanor Spangler, Brian J. Swanson, Kate Thomas, Jerome Treiman, Francesca Valencia, Alana Williams, Robert Zinke
Late Quaternary slip rates on the Sierra Madre fault zone and paleoseismic evidence on the size and frequency of past ruptures Late Quaternary slip rates on the Sierra Madre fault zone and paleoseismic evidence on the size and frequency of past ruptures
The Sierra Madre fault zone is a south-vergent, active reverse fault that accommodates shortening between basins on the northern margin of the Los Angeles region and the San Gabriel Mountains. The preservation of late Quaternary alluvial fill and fan surfaces in the hanging wall of the fault provides evidence of long-term uplift. Surface rupture from the 1971 Mw 6.6 San Fernando...
Authors
Reed J. Burgette, Katherine M. Scharer, Scott Lindvall
Airborne lidar and electro-optical imagery along surface ruptures of the 2019 Ridgecrest earthquake sequence, Southern California Airborne lidar and electro-optical imagery along surface ruptures of the 2019 Ridgecrest earthquake sequence, Southern California
Surface rupture from the 2019 Ridgecrest earthquake sequence, initially associated with the M 6.4 foreshock, occurred on July 4 on a ~17 km long, northeast-southwest oriented, left-lateral zone of faulting. Following the M 7.1 mainshock on July 5 (local time), extensive northwest-southeast-oriented, right-lateral faulting was then also mapped along a ~50 km long zone of faults, including...
Authors
Kenneth W. Hudnut, Benjamin A. Brooks, Katherine M. Scharer, Janis L. Hernandez, Timothy E. Dawson, Michael E. Oskin, J. Ramon Arrowsmith, Christine A. Goulet, Kelly Blake, Matthew A. Boggie, Stephan Bork, Craig L. Glennie, J.C. Fernandez-Diaz, Abhinav Singhania, Darren Hauser, Sven Sorhus
Late Quaternary slip rate of the Central Sierra Madre fault, southern California: Implications for slip partitioning and earthquake hazard Late Quaternary slip rate of the Central Sierra Madre fault, southern California: Implications for slip partitioning and earthquake hazard
The Sierra Madre fault system accommodates contraction within a large restraining bend area of the San Andreas fault along the northern margin of the Los Angeles metropolitan area in Southern California. Reverse slip along this fault system during earthquakes controls growth of the San Gabriel Mountains and poses a significant seismic hazard to the region. Here, we measure the late...
Authors
Reed J. Burgette, Austin Hanson, Katherine M. Scharer, Tammy M. Rittenour, Devin McPhillips
Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence
The Ridgecrest Earthquake sequence included a foreshock event on July 4 2019 (M6.4) and a M7.1 mainshock event on July 5 2019. These events occurred in the Eastern California Shear Zone, near Indian Wells Valley, south of China Lake and west of Searles Valley. GEER has partnered with several organizations to collect perishable data and document the important impacts of these events...
Authors
Scott J Brandenberg, Pengfei Wang, Chukwuebuka C Nweke, Kenneth Hudson, Silvia Mazzoni, Yousef Bozorgnia, Kenneth W. Hudnut, Craig A. Davis, Sean K Ahdi, Farzin Zareian, Jawad Fayaz, Richard D Koehler, Colin Chupik, Ian Pierce, Alana Williams, Sinan Akciz, Martin B Hudson, Tadahiro Kishida, Benjamin A. Brooks, Ryan D. Gold, Daniel J. Ponti, Katherine M. Scharer, Devin McPhillips, Christopher B. DuRoss, Todd Ericksen, Janis Hernandez, Jay Patton, Brian Olson, Timothy E. Dawson, Jerome Treiman, Kelly Blake, Jeffrey Buchhuber, Chris L M Madugo, Joseph Sun, Andrea Donnellan, Greg Lyzenga, Erik Conway
The current unlikely earthquake hiatus at California’s transform boundary paleoseismic sites The current unlikely earthquake hiatus at California’s transform boundary paleoseismic sites
Paleoseismic and historical earthquake records used to quantify earthquake recurrence rates can also be used to test the likelihood of seismically quiescent periods. At principal paleoseismic sites in California on the San Andreas, San Jacinto, Elsinore, and Hayward faults, no ground‐rupturing earthquake has occurred in the last 100 yr, yet this interval is about three times the average
Authors
Glenn Biasi, Katherine M. Scharer
The San Andreas Fault System--Complexities along a major transform fault system and relation to earthquake hazards The San Andreas Fault System--Complexities along a major transform fault system and relation to earthquake hazards
The San Andreas Fault System is a 1300-km-long transform boundary that accommodates motion between the North American and Pacific Plates. New technologies and data reveal rich details about the present configuration of faults, distribution of strain and associated seismic hazard on this complex network of faults. This contribution provides a brief summary of the geologic history of the...
Authors
Katherine M. Scharer, Ashley Streig
Quantifying uncertainty in cumulative surface slip along the Cucamonga Fault, a crustal thrust fault in southern California Quantifying uncertainty in cumulative surface slip along the Cucamonga Fault, a crustal thrust fault in southern California
Studies of historic earthquake ground surface ruptures show that displacements along strike are spatially variable. As a result, latest Quaternary slip rates developed from a spatially restricted set of cumulative displacement measurements may not accurately represent fault velocity. Here we examine the uncertainties associated with slip on the Cucamonga Fault, which is part of a network...
Authors
Devin McPhillips, Katherine M. Scharer
Characterizing the Los Angeles Aqueduct crossing of the San Andreas Fault for improved earthquake resilience Characterizing the Los Angeles Aqueduct crossing of the San Andreas Fault for improved earthquake resilience
The five-mile-long Elizabeth Tunnel, which crosses the San Andreas fault (SAF) zone near Lake Hughes, California, is part of the Los Angeles Aqueduct (LAA) that delivers water from Owens Valley to the City of Los Angeles. Geologic characterization of the Elizabeth Tunnel alignment is focused on developing a better understanding of fault displacement hazards at the SAF crossing to support...
Authors
Scott Lindvall, Scott Kerwin, Chris Heron, Craig A. Davis, Jeff Tyson, Jim Chestnut, Kevin Mass, Mike Farr, Katherine M. Scharer, Devin McPhillips
Evidence for coseismic subsidence events in a southern California coastal saltmarsh Evidence for coseismic subsidence events in a southern California coastal saltmarsh
Paleoenvironmental records from a southern California coastal saltmarsh reveal evidence for repeated late Holocene coseismic subsidence events. Field analysis of sediment gouge cores established discrete lithostratigraphic units extend across the wetland. Detailed sediment analyses reveal abrupt changes in lithology, percent total organic matter, grain size, and magnetic susceptibility
Authors
Robert Leeper, Brady P. Rhodes, Matthew E. Kirby, Katherine M. Scharer, Joseph A. Carlin, Eileen Hemphill-Haley, Simona Avnaim-Katav, Glen M. MacDonald, Scott W. Starratt, Angela Aranda
Ground-rupturing earthquakes on the northern Big Bend of the San Andreas Fault, California, 800 A.D. to Present Ground-rupturing earthquakes on the northern Big Bend of the San Andreas Fault, California, 800 A.D. to Present
Paleoseismic data on the timing of ground-rupturing earthquakes constrain the recurrence behavior of active faults and can provide insight on the rupture history of a fault if earthquakes dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 earthquakes that occurred along the Big Bend section of the southern San...
Authors
Katherine M. Scharer, Ray J. Weldon, Glenn Biasi, Ashley Streig, Thomas E. Fumal
Late Quaternary offset of alluvial fan surfaces along the Central Sierra Madre Fault, southern California Late Quaternary offset of alluvial fan surfaces along the Central Sierra Madre Fault, southern California
The Sierra Madre Fault is a reverse fault system along the southern flank of the San Gabriel Mountains near Los Angeles, California. This study focuses on the Central Sierra Madre Fault (CSMF) in an effort to provide numeric dating on surfaces with ages previously estimated from soil development alone. We have refined previous geomorphic mapping conducted in the western portion of the...
Authors
Reed J. Burgette, Austin Hanson, Katherine M. Scharer, Nikolas Midttun
Science and Products
Filter Total Items: 52
Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures Surface displacement distributions for the July 2019 Ridgecrest, California earthquake ruptures
Surface rupture in the 2019 Ridgecrest, California, earthquake sequence occurred along two orthogonal cross faults and includes dominantly left‐lateral and northeast‐striking rupture in the Mw 6.4 foreshock and dominantly right‐lateral and northwest‐striking rupture in the Mw 7.1 mainshock. We present >650 field‐based, surface‐displacement observations for these ruptures and synthesize...
Authors
Christopher B. DuRoss, Ryan D. Gold, Timothy E. Dawson, Katherine M. Scharer, Katherine J. Kendrick, Sinan Akciz, Stephen J. Angster, Jeffery Bachhuber, Steven Bacon, Scott E.K. Bennett, Luke Blair, Benjamin A. Brooks, Thomas Bullard, W. Paul Burgess, Colin Chupik, Michael DeFrisco, Jaime Delano, James D. Dolan, Erik Frost, Nick Graehl, Elizabeth Haddon, Alexandra Elise Hatem, Janis Hernandez, Christopher S. Hitchcock, Kennth Hudnut, Jessica Thompson Jobe, Richard D Koehler, Ozgur Kozaci, Tyler C. Ladinsky, Christopher Madugo, Devin McPhillips, Christopher Milliner, Alexander Morelan, Brian Olson, Jason Patton, Belle E. Philibosian, Alexandra J. Pickering, Ian Pierce, Daniel J. Ponti, Gordon G. Seitz, Eleanor Spangler, Brian J. Swanson, Kate Thomas, Jerome Treiman, Francesca Valencia, Alana Williams, Robert Zinke
Late Quaternary slip rates on the Sierra Madre fault zone and paleoseismic evidence on the size and frequency of past ruptures Late Quaternary slip rates on the Sierra Madre fault zone and paleoseismic evidence on the size and frequency of past ruptures
The Sierra Madre fault zone is a south-vergent, active reverse fault that accommodates shortening between basins on the northern margin of the Los Angeles region and the San Gabriel Mountains. The preservation of late Quaternary alluvial fill and fan surfaces in the hanging wall of the fault provides evidence of long-term uplift. Surface rupture from the 1971 Mw 6.6 San Fernando...
Authors
Reed J. Burgette, Katherine M. Scharer, Scott Lindvall
Airborne lidar and electro-optical imagery along surface ruptures of the 2019 Ridgecrest earthquake sequence, Southern California Airborne lidar and electro-optical imagery along surface ruptures of the 2019 Ridgecrest earthquake sequence, Southern California
Surface rupture from the 2019 Ridgecrest earthquake sequence, initially associated with the M 6.4 foreshock, occurred on July 4 on a ~17 km long, northeast-southwest oriented, left-lateral zone of faulting. Following the M 7.1 mainshock on July 5 (local time), extensive northwest-southeast-oriented, right-lateral faulting was then also mapped along a ~50 km long zone of faults, including...
Authors
Kenneth W. Hudnut, Benjamin A. Brooks, Katherine M. Scharer, Janis L. Hernandez, Timothy E. Dawson, Michael E. Oskin, J. Ramon Arrowsmith, Christine A. Goulet, Kelly Blake, Matthew A. Boggie, Stephan Bork, Craig L. Glennie, J.C. Fernandez-Diaz, Abhinav Singhania, Darren Hauser, Sven Sorhus
Late Quaternary slip rate of the Central Sierra Madre fault, southern California: Implications for slip partitioning and earthquake hazard Late Quaternary slip rate of the Central Sierra Madre fault, southern California: Implications for slip partitioning and earthquake hazard
The Sierra Madre fault system accommodates contraction within a large restraining bend area of the San Andreas fault along the northern margin of the Los Angeles metropolitan area in Southern California. Reverse slip along this fault system during earthquakes controls growth of the San Gabriel Mountains and poses a significant seismic hazard to the region. Here, we measure the late...
Authors
Reed J. Burgette, Austin Hanson, Katherine M. Scharer, Tammy M. Rittenour, Devin McPhillips
Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence Preliminary report on engineering and geological effects of the July 2019 Ridgecrest earthquake sequence
The Ridgecrest Earthquake sequence included a foreshock event on July 4 2019 (M6.4) and a M7.1 mainshock event on July 5 2019. These events occurred in the Eastern California Shear Zone, near Indian Wells Valley, south of China Lake and west of Searles Valley. GEER has partnered with several organizations to collect perishable data and document the important impacts of these events...
Authors
Scott J Brandenberg, Pengfei Wang, Chukwuebuka C Nweke, Kenneth Hudson, Silvia Mazzoni, Yousef Bozorgnia, Kenneth W. Hudnut, Craig A. Davis, Sean K Ahdi, Farzin Zareian, Jawad Fayaz, Richard D Koehler, Colin Chupik, Ian Pierce, Alana Williams, Sinan Akciz, Martin B Hudson, Tadahiro Kishida, Benjamin A. Brooks, Ryan D. Gold, Daniel J. Ponti, Katherine M. Scharer, Devin McPhillips, Christopher B. DuRoss, Todd Ericksen, Janis Hernandez, Jay Patton, Brian Olson, Timothy E. Dawson, Jerome Treiman, Kelly Blake, Jeffrey Buchhuber, Chris L M Madugo, Joseph Sun, Andrea Donnellan, Greg Lyzenga, Erik Conway
The current unlikely earthquake hiatus at California’s transform boundary paleoseismic sites The current unlikely earthquake hiatus at California’s transform boundary paleoseismic sites
Paleoseismic and historical earthquake records used to quantify earthquake recurrence rates can also be used to test the likelihood of seismically quiescent periods. At principal paleoseismic sites in California on the San Andreas, San Jacinto, Elsinore, and Hayward faults, no ground‐rupturing earthquake has occurred in the last 100 yr, yet this interval is about three times the average
Authors
Glenn Biasi, Katherine M. Scharer
The San Andreas Fault System--Complexities along a major transform fault system and relation to earthquake hazards The San Andreas Fault System--Complexities along a major transform fault system and relation to earthquake hazards
The San Andreas Fault System is a 1300-km-long transform boundary that accommodates motion between the North American and Pacific Plates. New technologies and data reveal rich details about the present configuration of faults, distribution of strain and associated seismic hazard on this complex network of faults. This contribution provides a brief summary of the geologic history of the...
Authors
Katherine M. Scharer, Ashley Streig
Quantifying uncertainty in cumulative surface slip along the Cucamonga Fault, a crustal thrust fault in southern California Quantifying uncertainty in cumulative surface slip along the Cucamonga Fault, a crustal thrust fault in southern California
Studies of historic earthquake ground surface ruptures show that displacements along strike are spatially variable. As a result, latest Quaternary slip rates developed from a spatially restricted set of cumulative displacement measurements may not accurately represent fault velocity. Here we examine the uncertainties associated with slip on the Cucamonga Fault, which is part of a network...
Authors
Devin McPhillips, Katherine M. Scharer
Characterizing the Los Angeles Aqueduct crossing of the San Andreas Fault for improved earthquake resilience Characterizing the Los Angeles Aqueduct crossing of the San Andreas Fault for improved earthquake resilience
The five-mile-long Elizabeth Tunnel, which crosses the San Andreas fault (SAF) zone near Lake Hughes, California, is part of the Los Angeles Aqueduct (LAA) that delivers water from Owens Valley to the City of Los Angeles. Geologic characterization of the Elizabeth Tunnel alignment is focused on developing a better understanding of fault displacement hazards at the SAF crossing to support...
Authors
Scott Lindvall, Scott Kerwin, Chris Heron, Craig A. Davis, Jeff Tyson, Jim Chestnut, Kevin Mass, Mike Farr, Katherine M. Scharer, Devin McPhillips
Evidence for coseismic subsidence events in a southern California coastal saltmarsh Evidence for coseismic subsidence events in a southern California coastal saltmarsh
Paleoenvironmental records from a southern California coastal saltmarsh reveal evidence for repeated late Holocene coseismic subsidence events. Field analysis of sediment gouge cores established discrete lithostratigraphic units extend across the wetland. Detailed sediment analyses reveal abrupt changes in lithology, percent total organic matter, grain size, and magnetic susceptibility
Authors
Robert Leeper, Brady P. Rhodes, Matthew E. Kirby, Katherine M. Scharer, Joseph A. Carlin, Eileen Hemphill-Haley, Simona Avnaim-Katav, Glen M. MacDonald, Scott W. Starratt, Angela Aranda
Ground-rupturing earthquakes on the northern Big Bend of the San Andreas Fault, California, 800 A.D. to Present Ground-rupturing earthquakes on the northern Big Bend of the San Andreas Fault, California, 800 A.D. to Present
Paleoseismic data on the timing of ground-rupturing earthquakes constrain the recurrence behavior of active faults and can provide insight on the rupture history of a fault if earthquakes dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 earthquakes that occurred along the Big Bend section of the southern San...
Authors
Katherine M. Scharer, Ray J. Weldon, Glenn Biasi, Ashley Streig, Thomas E. Fumal
Late Quaternary offset of alluvial fan surfaces along the Central Sierra Madre Fault, southern California Late Quaternary offset of alluvial fan surfaces along the Central Sierra Madre Fault, southern California
The Sierra Madre Fault is a reverse fault system along the southern flank of the San Gabriel Mountains near Los Angeles, California. This study focuses on the Central Sierra Madre Fault (CSMF) in an effort to provide numeric dating on surfaces with ages previously estimated from soil development alone. We have refined previous geomorphic mapping conducted in the western portion of the...
Authors
Reed J. Burgette, Austin Hanson, Katherine M. Scharer, Nikolas Midttun