Elizabeth S Cochran
Biography
Dr. Elizabeth S. Cochran is an observational seismologist at the United States Geological Survey in Pasadena, California. Elizabeth serves as Project Chief of the Induced Seismicity project in the Earthquake Science Center. Her research interests include investigating the link between increased earthquake rates in the Central and Eastern U.S. and energy production activities, specifically disposal of large volumes of wastewater. She also conducts research on earthquake early warning, earthquake triggering, rupture processes, and seismic wave propagation, and has led several large seismic deployments following significant earthquakes in the United States. Elizabeth previously served as Chief Scientist of the ShakeAlert Earthquake Early Warning project working to develop a system to warn of incoming ground shaking from moderate to large earthquakes. She was also the co-founder of the Quake Catcher Network, a crowd-sourced seismic network that uses low cost sensors connected to desktop or inside of laptops and phones located in homes, offices and schools to detect earthquakes. Elizabeth received a B.S. in geophysics from University of California, Santa Barbara and a M.Sc. and Ph.D. in geophysics and space physics from the University of California, Los Angeles. In 2010, she was recognized with a Presidential Early Career Award for Scientists and Engineers (PECASE), which is the highest honor bestowed by the United States government on outstanding scientists and engineers in the early stages of their independent research careers.
Experience
2011 – Present Research Geophysicist, US Geological Survey
2011 – Present Visiting Associate in Geophysics, California Institute of Technology
2007 – 2011 Assistant Professor, Department of Earth Sciences, University of California, Riverside
2005 – 2007 Postdoctoral Scholar, Institute of Geophysics and Planetary Physics, Scripps
2000 – 2005 Research Assist./Assoc., Department of Earth and Space Science, University of California, Los Angeles
Education
University of California, Santa Barbara Geophysics B.S., 2000
University of California, Los Angeles Geophysics and Space Physics M.S., 2003
University of California, Los Angeles Geophysics and Space Physics Ph.D., 2005
Honors and Activities
· Presidential Early Career Award for Scientists and Engineers (PECASE), 2010.
· NSF Faculty Early Career Development (CAREER) Award, 2010.
· Geological Society of America, Subaru Outstanding Woman in Science Award, 2006.
· Young Fellow of the Institute of Geophysics and Planetary Physics, 2004.
· Southern California Earthquake Center Seismology Discipline Co-Chair, 2009-2017.
· IRIS Standing Committee Member; Data Management (2008-2010), Education and Public Outreach (2012-2014).
Science and Products
Earthquake Early Warning – Fine-Tuning for Best Alerts
The goal of an earthquake early warning (EEW) system is to provide an alert to people and automatic systems after an earthquake begins but before the shaking reaches their location. As the USGS and its partners are developing an EEW system, called ShakeAlert®, for the West Coast, the benefits, costs, capabilities, and limitations are being investigated. Two recent studies explored the...
3D fault architecture controls the dynamism of earthquake swarm
The vibrant evolutionary patterns made by earthquake swarms are incompatible with standard, effectively two-dimensional (2D) models for general fault architecture. We leverage advances in earthquake monitoring with a deep-learning algorithm to image a fault zone hosting a 4-year-long swarm in southern California. We infer that fluids are naturally...
Ross, Z.; Cochran, Elizabeth S.; Trugman, D.; Smith, Jonathan D. Minimal clustering of injection-induced earthquakes observed with a large-n seismic array
The clustering behavior of injection‐induced earthquakes is examined using one month of data recorded by the LArge‐n">n Seismic Survey in Oklahoma (LASSO) array. The 1829‐node seismic array was deployed in a 25  km×32  km">25 km×32 km area of active saltwater disposal in...
Cochran, Elizabeth S.; Wickham-Piotrowski, A.; Kemna, K.; Harrington, R.M; Dougherty, S.; Pena Castro, A. Activation of optimally and unfavourably oriented faults in a uniform local stress field during the 2011 Prague, Oklahoma, sequence
The orientations of faults activated relative to the local principal stress directions can provide insights into the role of pore pressure changes in induced earthquake sequences. Here, we examine the 2011 M 5.7 Prague earthquake sequence that was induced by nearby wastewater disposal. We estimate the local principal compressive stress...
Cochran, Elizabeth S.; Skoumal, Robert; McPhillips, Devin; Ross, Z.; Keranen, Katie M. The U.S. Geological Survey’s Rapid Seismic Array Deployment for the 2019 Ridgecrest Earthquake Sequence
Rapid seismic deployments following large earthquakes capture ephemeral near‐field recordings of aftershocks and ambient noise that can provide valuable data for seismological studies. The U.S. Geological Survey installed 19 temporary seismic stations following the 4 July 2019 Mw 6.4 and 6 July 2019 (UTC) Mw 7.1 earthquakes near the city of...
Cochran, Elizabeth S.; Wolin, Emily; McNamara, Daniel E.; Yong, Alan; Wilson, David C.; Alvarez, Mark; Van Der Elst, Nicholas; McClain, Adria Ruth; Steidl, Jamison Haase How often can Earthquake Early Warning systems alert sites with high intensity ground motion?
Although numerous Earthquake Early Warning (EEW) algorithms have been developed we still lack a detailed understanding of how often and under what circumstances useful ground motion alerts can be provided to end-users. Here we analyze the alerting performance of the PLUM, EPIC and FinDer algorithms by running them retrospectively on the seismic...
Meier, M.-A.; Kodera, Y.; Bose, M.; Chung, A. I.; Hoshiba, M.; Cochran, Elizabeth S.; Minson, Sarah E.; Hauksson, E.; Heaton, T. How low should we go when warning for earthquakes?
A key goal of earthquake early warning (EEW) systems is to alert populations who may be affected by a particular level of ground shaking so that they can take action to reduce impacts of that shaking, such as injuries, damages to physical infrastructure, or emotional distress. Most EEW systems work by rapidly determining the location and size of...
Cochran, Elizabeth S.; Husker, Allen L. The LArge-n Seismic Survey in Oklahoma (LASSO) experiment
In 2016, the U.S. Geological Survey deployed more than 1,800 vertical-component nodal seismometers in Grant County, Oklahoma to study induced seismic activity associated with production of the Mississippi Limestone Play. The LArge-n Seismic Survey in Oklahoma (LASSO) array operated for approximately one month, covering a 25-km-by-32-km region with...
Dougherty, S.; Cochran, Elizabeth S.; Harrington, R. M. Depth determination of the 2010 El Mayor‐Cucapah earthquake sequence (M ≥ 4.0)
The 2010 MW 7.2 El Mayor‐Cucapah earthquake ruptured a zone of ~120 km in length in northern Baja California. The geographic distribution of this earthquake sequence was well constrained by waveform relocation. The depth distribution, however, was poorly determined as it is near the edge of, or outside, the Southern California Seismic...
Yu, C.; Hauksson, E.; Zhan, Z.; Cochran, Elizabeth S.; Helmberger, D. Determining Moho depth beneath sedimentary basins using regional Pn multiples
The study of the Moho beneath thick sedimentary basins involving natural earthquakes is challenging, as low‐velocity materials often cause strong reverberations that mask Moho signals. Here, we develop a method to determine the depth of the Moho by taking advantage of the presence of the sediments. The method utilizes the first Pn crustal multiple...
Yu, C.; Zhan, Z.; Hauksson, E.; Cochran, Elizabeth S.; Helmberger, D. Event detection performance of the PLUM earthquake early warning algorithm in southern California
We test the Japanese ground‐motion‐based earthquake early warning (EEW) algorithm, propagation of local undamped motion (PLUM), in southern California with application to the U.S. ShakeAlert system. In late 2018, ShakeAlert began limited public alerting in Los Angeles to areas of expected modified Mercalli intensity (IMMI) 4.0+ for magnitude 5.0...
Cochran, Elizabeth S.; Bunn, Julian; Minson, Sarah E.; Baltay, Annemarie S.; Kilb, Deborah L.; Kodera, Y.; Hoshiba, Mitsuyuki Peak ground displacement saturates exactly when expected: Implications for earthquake early warning
The scaling of rupture properties with magnitude is of critical importance to earthquake early warning (EEW) systems that rely on source characterization using limited snapshots of waveform data. ShakeAlert, a prototype EEW system that is being developed for the western United States, provides real-time estimates of earthquake magnitude based on P...
Trugman, Daniel T.; Page, Morgan T.; Minson, Sarah E.; Cochran, Elizabeth S. Slow-growing and extended-duration seismicity swarms: Reactivating joints or foliations in the Cahuilla Valley Pluton, Central Peninsular Ranges, Southern California
Three prolific earthquake swarms and numerous smaller ones have occurred since 1980 in the Mesozoic igneous plutonic rocks of the Perris block of the Peninsular Ranges, Southern California. The major swarms occurred in 1980–1981, 1983–1984, and 2016–2018, with the latest swarm still ongoing. These swarms have no clear mainshock, with the largest...
Hauksson, E.; Ross, Z.; Cochran, Elizabeth S.
President Obama Honors Quake-Catcher Network Inventor Elizabeth Cochran
Dr. Elizabeth Cochran, a geophysicist with the U.S. Geological Survey, was named one of President Obama’s recipients of the Presidential Early Career Awards for Scientists and Engineers, the highest honor bestowed by the United States government on science and engineering professionals in the early stages of their independent research careers.