Ruth Harris is a senior scientist with the U.S. Geological Survey’s Earthquake Science Center. She received her S.B. from MIT, her M.S. from Cornell University, and her Ph.D. from UC Santa Barbara. Her research focuses on understanding large earthquakes, what causes them to start, stop, and trigger other earthquakes, and determining how they generate strong ground shaking.
Her approach involves computer simulations of earthquake rupture dynamics, and investigations of geophysical and geological field and laboratory observations. She has had a long-time interest in creeping faults, starting from the beginning of her earthquake career working on the Parkfield region of the San Andreas fault, and continuing to more recent time with her 2017 review article on creeping faults, and her 2021 paper simulating scenario earthquakes on the San Francisco Bay Area’s Rodgers Creek, Hayward, and Calaveras faults.
Ruth leads a 30-scientists USGS project which investigates earthquake mechanics from a range of perspectives including field observations and rock mechanics lab experiments, produces the USGS’s aftershock probabilities, and studies subduction zones along with their tsunamigenesis.
She served on the Board of Directors of the Seismological Society of America (SSA) for 11 years, including as President from 2015 to 2016. She is a three-decades member of the Southern California Earthquake Center, served as a SCEC science planning committee member for more than 10 years, and is a USGS liaison to the SCEC Board of Directors.
Ruth served as an Associate Editor for the American Geophysical Union’s (AGU) Journal of Geophysical Research from 1997-2001, as an Editor for AGU’s Geophysical Research Letters from 2009-2012, and as of September 2021 she is an Associate Editor for SSA’s journal, The Seismic Record. For her work on earthquake science, she received the U.S. Department of the Interior’s Meritorious Service Award in 2011, the UCSB Department of Earth Science’s Distinguished Alumna Award in 2016, and was elected a Fellow of the American Geophysical Union in 2019.
Ruth's science accomplishments include:
*Leadership of the long-running international SCEC-USGS dynamic rupture group
*Development of the stress shadow hypothesis and coining of the "stress shadow" term, with R. Simpson
*The first simulations of dynamic multi-fault earthquake rupture, with S. Day and R. Archuleta
*The first simulations of dynamic earthquake rupture for damage zones and for bimaterials, assuming a drop in friction, with results producing occasional supershear rupture speeds, and producing evidence that material contrast alone does not predict earthquake rupture propagation direction, with S. Day and D.J. Andrews
*The first imaging of the Juan de Fuca plate subducted at depth beneath southern Oregon, with H.M. Iyer and P. Dawson
*The first detailed inversions of geodetic data for 2D slip on a fault, with P. Segall
Links to many of Ruth’s publications can be found in Google Scholar and ORCID.
If you do not have access to her publications, please email her.
Science and Products
60 years and beyond of Reviews of Geophysics
January 12, 2023 SCEC workshop, Dynamic Rupture TAG – Investigating new ideas in earthquake source mechanics(SCEC Project 22157)
Earthquakes in the shadows: Why aftershocks occur at surprising locations
Working with dynamic earthquake rupture models: A practical guide
Dynamic Rupture TAG – The 2021 Ingredients Workshop – Stress Conditions (SCEC Project 21127)
Final report to SCEC on the October 27, 2020 SCEC workshop ‘dynamic rupture TAG – The 2020 ingredients workshop – Rock properties (SCEC rroject 20188)’
A geology and geodesy based model of dynamic earthquake rupture on the Rodgers Creek‐Hayward‐Calaveras Fault System, California
Dynamic rupture simulations of the M6.4 and M7.1 July 2019 Ridgecrest, California earthquakes
Final report to SCEC on the January 8, 2020 SCEC workshop 'Dynamic Rupture TAG Ingredients Workshop – Fault Friction (SCEC Project 19121)'
The community code verification exercise for simulating sequences of earthquakes and aseismic slip (SEAS)
A suite of exercises for verifying dynamic earthquake rupture codes
Large earthquakes and creeping faults
Science and Products
Filter Total Items: 53
60 years and beyond of Reviews of GeophysicsReviews of Geophysics is an AGU journal, first established in February 1963. It is a hybrid open access invitation-only journal that publishes comprehensive review articles across various disciplines within the Earth and Space Sciences. The selection criteria are rigorous and many submissions are declined without review. The journal is the highest ranked in the fields of Geochemistry and GeophysicAuthorsFabio Florindo, Valerio Acocella, Ann Marie Carlton, Paolo D’Odorico, Qingyun Duan, Andrew Gettelman, Jasper Halekas, Ruth A. Harris, Gesine Mollenhauer, Alan Robock, Claudine Stirling, Yusuke Yokoyama
January 12, 2023 SCEC workshop, Dynamic Rupture TAG – Investigating new ideas in earthquake source mechanics(SCEC Project 22157)The Southern California Earthquake Center (SCEC) workshop “Dynamic Rupture TAG – Investigating New Ideas in Earthquake Source Mechanics” was convened on Zoom on January 12, 2023. A total of 60 people participated. Our workshop attendees included scientists from 28 institutions and 11 countries (United States of America, Australia, Brazil, Czech Republic, China, France, Germany, Japan, New ZealanAuthorsRuth A. Harris, Michael Barall
Earthquakes in the shadows: Why aftershocks occur at surprising locationsFor decades there has been a debate about the relative effects of dynamic versus static stress triggering of aftershocks. According to the static Coulomb stress change hypothesis, aftershocks should not occur in stress shadows—regions where static Coulomb stress has been reduced. We show that static stress shadows substantially influence aftershock occurrence following three M ≥ 7 California mainsAuthorsJeanne L. Hardebeck, Ruth A. Harris
Working with dynamic earthquake rupture models: A practical guideDynamic rupture models are physics‐based simulations that couple fracture mechanics to wave propagation and are used to explain specific earthquake observations or to generate a suite of predictions to understand the influence of frictional, geometrical, stress, and material parameters. These simulations can model single earthquakes or multiple earthquake cycles. The objective of this article is tAuthorsMarlon D. Ramos, Prithvi Thakur, Yihe Huang, Ruth A. Harris, Kenny J. Ryan
Dynamic Rupture TAG – The 2021 Ingredients Workshop – Stress Conditions (SCEC Project 21127)No abstract available.AuthorsRuth A. Harris, Michael Barall
Final report to SCEC on the October 27, 2020 SCEC workshop ‘dynamic rupture TAG – The 2020 ingredients workshop – Rock properties (SCEC rroject 20188)’This workshop was the third in our series of four SCEC5 workshops designed to evaluate the importance of each of the four ingredients required for dynamic earthquake rupture simulations. The four ingredients are: fault geometry, fault friction, rock properties, and initial stress conditions (Figure 1). The previous two workshops in the ‘ingredients’ series were the November 2018 SCEC workshop thAuthorsRuth A. Harris, Michael Barall
A geology and geodesy based model of dynamic earthquake rupture on the Rodgers Creek‐Hayward‐Calaveras Fault System, CaliforniaThe Hayward fault in California's San Francisco Bay area produces large earthquakes, with the last occurring in 1868. We examine how physics‐based dynamic rupture modeling can be used to numerically simulate large earthquakes on not only the Hayward fault, but also its connected companions to the north and south, the Rodgers Creek and Calaveras faults. Equipped with a wealth of images of this faulAuthorsRuth A. Harris, Michael Barall, David A. Lockner, Diane E. Moore, David A. Ponce, Russell Graymer, Gareth J. Funning, Carolyn A. Morrow, Christodoulos Kyriakopoulos, Donna Eberhart-Phillips
Dynamic rupture simulations of the M6.4 and M7.1 July 2019 Ridgecrest, California earthquakesThe largest earthquakes of the 2019 Ridgecrest, California, sequence were a M 6.4 left‐lateral rupture followed 34 hr later by a M 7.1 on a perpendicular right‐lateral fault. We use dynamic rupture modeling to address the questions of why the first earthquake did not propagate through the right‐lateral fault in one larger event, whether stress changes from the M 6.4 were necessary for the M 7.1 toAuthorsJulian C. Lozos, Ruth A. Harris
Final report to SCEC on the January 8, 2020 SCEC workshop 'Dynamic Rupture TAG Ingredients Workshop – Fault Friction (SCEC Project 19121)'This workshop was the second of a series of four SCEC5 workshops designed to evaluate the importance of each of the four ingredients required for dynamic earthquake rupture simulations. The four ingredients are: initial stress conditions, fault geometry, rock properties, and fault friction (Figure 1). This workshop included a range of views of how fault friction operates in the Earth, based on iAuthorsRuth A. Harris, Michael Barall
The community code verification exercise for simulating sequences of earthquakes and aseismic slip (SEAS)Numerical simulations of sequences of earthquakes and aseismic slip (SEAS) have made great progress over past decades to address important questions in earthquake physics. However, significant challenges in SEAS modeling remain in resolving multiscale interactions between earthquake nucleation, dynamic rupture, and aseismic slip, and understanding physical factors controlling observables such as sAuthorsBrittany Erickson, Junle Jiang, Michael Barall, Nadia Lapusta, Eric Dunham, Ruth A. Harris, Lauren Abrahams, Kali Allison, Jean-Paul Ampuero, Sylvain Barbot, Camilla Cattania, Ahmed Elbanna, Yuri Fialko, Benjamin Idini, Jeremy Kozdon, Valere Lambert, Yajing Liu, Yingdi Luo, Xiao Ma, Maricela Best McKay, Paul Segall, Pengsheng Shi, Martijn van den Ende, Mengjie Wei
A suite of exercises for verifying dynamic earthquake rupture codesWe describe a set of benchmark exercises that are designed to test if computer codes that simulate dynamic earthquake rupture are working as intended. These types of computer codes are often used to understand how earthquakes operate, and they produce simulation results that include earthquake size, amounts of fault slip, and the patterns of ground shaking and crustal deformation. The benchmark exAuthorsRuth A. Harris, Michael Barall, Brad T. Aagaard, Shuo Ma, Daniel Roten, Kim Olsen, Benchun Duan, Dunyu Liu, Bin Luo, Kangchen Bai, Jean-Paul Ampuero, Yoshihiro Kaneko, Alice-Agnes Gabriel, Kenneth Duru, Thomas Ulrich, Stephanie Wollherr, Zheqiang Shi, Eric Dunham, Sam Bydlon, Zhenguo Zhang, Xiaofei Chen, Surendra N. Somala, Christian Pelties, Josue Tago, Victor Manuel Cruz-Atienza, Jeremy Kozdon, Eric Daub, Khurram Aslam, Yuko Kase, Kyle Withers, Luis Dalguer
Large earthquakes and creeping faultsFaults are ubiquitous throughout the Earth's crust. The majority are silent for decades to centuries, until they suddenly rupture and produce earthquakes. With a focus on shallow continental active-tectonic regions, this paper reviews a subset of faults that have a different behavior. These unusual faults slowly creep for long periods of time and produce many small earthquakes. The presence of fauAuthorsRuth A. Harris