Han, L., Peng, Z., Johnson, C. W., Pollitz, F.F., Wang, B., Li, L., Wang, B., Wu, J., Li, Q., and Wei, H., "Shallow microearthquakes near Chongqing, China triggered by the Rayleigh waves of the 2015 M7.8 Gorkha, Nepal earthquake", Earth Planet. Sci. Lett., 479, 231-240, 2017.
Fred F Pollitz
Biography
Fred Pollitz is a research geophysicist with the U.S. Geological Survey. He received his Ph.D in Geophysics (long-period seismology) from Princeton University in 1989, advised by Tony Dahlen. As a postdoctoral researcher he switched focus to crustal deformation studies, motivated initially through collaboration with Dr. Selwyn Sacks at the Carnegie Institution of Washington. With the USGS since 2000, he has continued to work on problems related to crustal deformation and long-period seismology.
Education:
B.Sc. in Mathematics, Massachusetts Institute of Technology, Cambridge, MA USA (1984)
B.Sc. in Geophysics, Massachusetts Institute of Technology, Cambridge, MA USA (1984)
Ph.D. in Geophysics, Princeton University, Princeton, NJ USA (1989)
Professional Experience:
1997 to 2000: Postdoctoral Researcher, University of California, Davis
1995 to 1997: Isaac Newton Trust Postdoctoral Fellow, University of Cambridge, England
1993 to 1995: Alexander von Humboldt Postdoctoral Fellow, Geophysical Institute, Karlsruhe, Germany
1992 to 1993: CNRS Research Associate, Laboratoire de Sismologie, Institut de Physique du Globe, Paris
1989 to 1991: Postdoctoral Fellow, Department of Terrestrial Magnetism, Carnegie Institution of Washington
Honors and Offices:
2010 - First author of two of the 20 most cited `earthquake’ papers of the period
2000-2010
(http://www.sciencewatch.com/ana/st/earthquakes2/papers10yr/)
2002 - 2013 - Associate Editor, Bulletin of the Seismological Society of America
1998 - 2001 - Associate Editor, Journal of Geophysical Research
Publications
Pollitz, F. F.; Kobayashi, T.; Yarai, H.; Shibazaki, B.; Matsumoto, T., Viscoelastic lower crust and mantle relaxation following the 14–16 April 2016 Kumamoto, Japan, earthquake sequence, Geophysical Research Letters, 44, 8795-8803, http://onlinelibrary.wiley.com/doi/10.1002/2017GL074783/abstract (2017).
Pollitz, F.F. and Cattania, C., Connecting crustal seismicity and earthquake-driven stress evolution in southern California, J. Geophys. Res. Solid Earth, 122, 6473–6490, doi:10.1002/2017JB014200, http://onlinelibrary.wiley.com/doi/10.1002/2017JB014200/full (2017).
Pollitz, F.F., Wicks, C., Schoenball, M., Ellsworth, W., and Murray, M., Geodetic slip model of the 3 September 2016 Mw 5.8 Pawnee, Oklahoma, earthquake: Evidence for fault zone collapse, Seismol. Res. Lett., doi:10.1785/0220170002, http://srl.geoscienceworld.org/content/early/2017/04/28/0220170002/artic... (2017).
Pollitz, F.F. and Evans, E.L., Implications of the earthquake cycle for inferring fault locking on the Cascadia megathrust, Geophys. J. Int., 209, 167-185, doi:10.1093/gji/ggx009, https://academic.oup.com/gji/article/209/1/167/2893457/Implications-of-t... (2017).
Pollitz, F.F., A note on adding viscoelasticity to earthquake simulators, Bull. Seismol. Soc. Am., 107, doi:10.1785/0120160192, http://www.bssaonline.org/content/107/1/468.abstract (2016).
Han, S.-H., Sauber, J., and Pollitz, F., Postseismic gravity change after the 2006-2007 great earthquake doublet and constraints on the asthenosphere structure in the central Kuril Islands, Geophys. Res. Lett., doi: 10.1002/2016GL068167 (2016). [Link]
Evans, E.L., Thatcher, W.R., Pollitz, F.F., and Murray, J.R., Persistent slip rate discrepancies in the eastern California (USA) shear zone, Geology, 44, doi:10.1130/G37967.1 (2016).
Pollitz, F.F., and Mooney, W.D., Seismic velocity structure of the crust and shallow mantle of the Central and Eastern United States by seismic surface wave imaging, Geophys. Res. Lett., 42, 1-9, doi:10.1002/2015GL066637 (2016). [Link]
Huang, M.-H., Burgmann, R., and Pollitz, F.F., Lithospheric rheology constrained from twenty-five years of postseismic deformation following the 1989 Mw 6.9 Loma Prieta earthquake, Earth Planet. Sci. Lett., 435, 147-158 (2016).
Pollitz, F.F., Ellsworth, W., and Rubinstein, J., Interpretation of S waves generated by near-surface chemical explosions at SAFOD, Bull. Seismol. Soc. Am, 105, 2835-2851 (2015). [Link]
Brocher, T.M., Baltay, A. S., Hardebeck, J. L., Pollitz, F. F., Murray, J. R., Llenos, A. L., Schwartz, D. P., Blair, J. L., Ponti, D. J., Lienkaemper, J. J., Langenheim, V. E., Dawson, T. E., Hudnut, K. W., Shelly, D. R., Dreger, D., Boatwright, J., Aagaard, B. T., Wald, D. J., Allen, R. M., Barnhart, W. D., Knudsen, K. L., Brooks, B. A., and Scharer, K. M., The M6.0 24 August 2014 South Napa Earthquake,Seism. Res. Lett., 86(2A), doi:10.1785/0220150004 (2015). [Download File]
Pollitz, F.F., Post-earthquake relaxation evidence for laterally variable viscoelastic structure and water content in the southern California mantle, J. Geophys. Res., 120, 2672-2696, doi:10.1002/2014JB011603 (2015). [Download File]
Johnson, C.W., Burgmann, R., and Pollitz, F. F., Global catalog analysis shows that dynamic triggering of remote M≥5.5 earthquakes is rare, J. Geophys. Res., 120, doi:10.1002/2014JB011788 (2015).[Download File]
Han, S.-C., Sauber, J., and Pollitz, F., Coseismic compression/dilatation and viscoelastic uplift/subsidence following the 2012 Indian Ocean earthquakes quantified from satellite gravity observations, Geophys. Res. Lett., 42, doi:10.1002/2015GL063819 (2015). [Download File]
Pollitz, F. F., Post-earthquake relaxation using a spectral element method: 2.5-D case, Geophys. J. Int., doi: 10.1093/gji/ggu114 (2014). [Link]
Pollitz, F.F., Bürgmann, R., Stein, R.S., and Sevilgen, V., The Profound Reach of the 11 April 2012 M 8.6 Indian Ocean Earthquake: Short-Term Global Triggering Followed by a Longer-Term Global Shadow, Bull. Seismol. Soc. Am., doi: 10.1785/0120130078 (2014) [Download File]
Porritt, R.W., Allen, R.M., and Pollitz, F.F., Seismic imaging east of the Rocky Mountains with USArray, Earth and Planetary Science Letters, doi:10.1016/j.epsl.2013.10.034 (2014). [Download File]
Pollitz, F.F. and Mooney, W.D., Regional seismic wave propagation from the M5.8 August 23, 2011 Mineral, Virginia earthquake, GSA Special Volume on the Mineral, Virginia earthquake, v. 509, Chapter 6 (2014). [Download File]
Han, S.-C., Sauber, J., and Pollitz, F.F., Broadscale postseismic gravity change following the 2011 Tohoku-Oki earthquake and implication for deformation by viscoelastic relaxation and afterslip, Geophys. Res. Lett., DOI: 10.1002/2014GL060905 (2014). [Download File]
Shirzaei, M., Burgmann, R., Uchida, N., Hu, Y., Pollitz, F., and Matsuzawa, T., Seismic versus aseismic slip: Probing mechanical properties of the northeast subduction zone, Earth Planet. Sci. Lett., 406, 7-13 (2014). [Download File]
Pollitz, F.F. and Mooney, W., Seismic structure of the central US crust and upper mantle: Uniqueness of the Reelfoot Rift, Earth Planet. Sci. Lett., (2013) http://dx.doi.org/10.1016/j.epsl.2013.05.042i[Download File]
Hearn, E.H., Pollitz, F.F., Thatcher, W.R., and Onishi, C.T., How do `ghost transients’ from past earthquakes affect GPS slip rate estimates on southern California faults?, Geochem. Geophys. Geosys., DOI: 10.1002/ggge.20080. [Download File]
Pollitz, F.F., Wech, A., Kao, H., and Burgmann, R., Annual modulation of non-volcanic tremor in northern Cascadia, J. Geophys. Res., 118, 2445-2459 (2013). [Download File]
Pollitz, F.F., Rubinstein, J., and Ellsworth, W., Source characterization of near-surface chemical explosions at SAFOD, Bull. Seismol. Soc. Am., 102, 1348-1360 (2012). [Link]
Volkan Sevilgen, Ross S. Stein, and Fred F. Pollitz, Stress imparted by the great 2004 Sumatra earthquake shut down transforms and activated rifts up to 400 km away in the Andaman Sea, Proc Natl Acad Sci USA, doi: 10.1073/pnas.1208799109 [includes animation] [Link]
Pollitz, F.F., Stein, R.S. (USGS), Sevilgen, V., and Bürgmann, R., The 11 April 2012 M=8.6 East Indian Ocean earthquake triggered large aftershocks worldwide, Nature, doi: 10.1038/nature11504[Download File]
Pollitz, F.F., Burgmann, R., and Thatcher, W., Illumination of rheological mantle heterogeneity by the M7.2 2010 El Mayor-Cucapah earthquake, Geochem. Geophys. Geosys., 13, DOI: 10.1029/2012GC004139 [Download File]
Pollitz, F.F., High-frequency Born synthetic seismograms based on coupled normal modes, Geophys. J. Int., 187, 1420-1442 (2011). [Link]
Pollitz, F.F., Brooks, B., Tong, X., Bevis, M.G., Foster, J.H., Burgmann, R., Smalley, R., Vigny, C., Socquet, A., Ruegg, J.-C., Campos, J., Barrientos, S., Parra, H., Baez Soto, J. C., Cimbaro, S., and Blanco, M., Coseismic slip distribution of the February 27, 2010 Mw 8.8 Maule, Chile earthquake, Geophys. Res. Lett., L09309, doi:10.1029/2011GL047065 (2011). [Download File]
Obrebski, M., Allen, R., Pollitz, F.F., and Hung, S.-H., Lithosphere-asthenosphere interaction beneath the western US from the joint inversion of body-wave travel times and surface-wave phase velocites, Geophys. J. Int., 185, 1003-1021 (2011). [Download File]
Pollitz, F.F., Epistemic uncertainty in California-wide synthetic seismicity simulations, Bull. Seismol. Soc. Am., 101, 2481-2498 (2011). [Download File]
Ryder, I., Burgmann, R., and Pollitz, F.F., Lower crustal relaxation beneath the Tibetan Plateau and Qaidam Basin following the 2001 Kokoxili earthquake, Geophys. J. Int., 187, 613-630 (2011). [Download File]
Pollitz, F.F., Burgmann, R., and Banerjee, P., Geodetic slip model of the 2011 M9.0 Tohoku Earthquake, Geophys. Res. Lett., 38, doi:10.1029/2011GL048632 (2011). [Download File]
Pollitz, F.F., Probabilistic seismic hazard in the San Francisco Bay area based on seismicity simulation, Proceedings of the Third Conference on Earthquake Hazards in the Eastern San Francisco Bay area, California Geological Survey (2010).
Pollitz, F.F., and Thatcher, W. On the resolution of shallow mantle viscosity structure using post-earthquake relaxation data: Application to the 1999 Hector Mine, California, earthquake, J. Geophys. Res., Q06008, doi:10.1029/2010JB007405 (2010). [Download File]
Panet, I., Pollitz, F.F., Mikhailov, V., Diament, M., Banerjee, P., and Grijalva, K., Upper mantle rheology from GRACE and GPS postseismic deformation after the 2004 Sumatra-Andaman earthquake, Geochem. Geophys. Geosyst., Q06008, doi:10.1029/2009GC002905 (2010). [Download File]
Pollitz, F.F., McCrory, P., Wilson, D., Svarc, J., Puskas, C., and Smith, R.B., Viscoelastic-cycle model of interseismic deformation in the northwestern United States, Geophys. J. Int., 181, 665-696 (2010).[Download File]
Pollitz, F.F. and Snoke, J.A., Rayleigh-wave phase-velocity maps and three-dimensional shear-velocity structure of the western US from local non-plane surface-wave tomography, Geophys. J. Int., 180, 1153-1169 (2010). [Download File]
Pollitz, F.F., A viscoelastic earthquake simulator, with application to the San Francisco Bay region, Bull. Seismol. Soc. Am., 99, 1760-1785 (2009). [Download File]
Boyd, O.S., Pollitz, F.F., Zeng, Y., Hardebeck, J.L., Bufe, C.G., and Wesson, R.L., Time-dependent probabilistic hazard maps for Alaska, AGU Monograph on Tectonics of Alaska (2008).
Pollitz, F.F., McCrory, P., Svarc, J., and Murray, J.R., Dislocation models of interseismic deformation in the western United States, J. Geophys. Res., 113, B04413, doi:10.1029/2007JB005174 (2008).
Pollitz, F.F., Banerjee, P., Grijalva, K., Nagarajan, B., and Burgmann, R., Effect of 3D viscoelastic structure on postsiesmic relaxation from the M=9.2 Sumatra earthquake, Geophys. J. Int., 172, 189-204 (2008). [Download File]
Thatcher, W. and Pollitz, F.F., Temporal evolution of continental lithospheric strength in actively deforming regions, GSA Today, 18, 4-11 (2008). [Download File]
Pollitz, F.F. and Schwartz, D., Probabilistic seismic hazard in the San Francisco Bay area based on a simplified viscoelastic-cycle model of fault interactions, J. Geophys. Res., 113, B05409, doi:10.1029/2007JB005227 (2008). [Download File]
Han, S.-C., Sauber, J, Luthcke, S. B., Ji, C., and Pollitz, F. F., Implications of postseismic gravity change following the great 2004 Sumatra-Andaman earthquake from the regional harmonic analysis of GRACE intersatellite tracking data, J. Geophys. Res., 113, No. B11, B11413, doi:10.1029/2008JB005705 (2008). [Download File]
Pollitz, F.F., Finite frequency tomography of crustal structure in the San Francisco Bay region, Geophys. J. Int., 171, 630-656 (2007). [Download File]
Panet, I., Mikhailov, V., Diament, M., de Viron, O., King, G., Pollitz, F., Holschneider, M., and Biancale, R., Co-seismic and post-seismic signatures of tha Sumatra December 2004 and March 2005 earthquakes in GRACE satellite gravity, Geophys. J. Int., doi:10.1111/j.1365-246X.2007.03525.x (2007). [Download File]
Geist, E.L., Titov, V.V., Arcas, D., Pollitz, F.F., and Bilek, S.L., Implications of the December 26, 2004 Sumatra-Andaman earthquake on tsunami forecast and assessment models for great subduction zone earthquakes, Bull. Seismol. Soc. Am., 97, S240-S270 (2007). [Download File]
Banerjee, P., Pollitz, F.F., and Burgmann, R., Coseismic slip distributions of the 26 December 2004 Sumatra-Andaman and 28 March 2005 Nias earthquakes from GPS static offsets, Bull. Seismol. Soc. Am., 97, S86-S102 (2007). [Download File]
Pollitz, F.F. and Johnston, M.J.S., Direct test of static-stress versus dynamic-stress triggering of aftershocks, Geophys. Res. Lett., 33, L15318, doi:10.1029/2006GL026764 (2006). [Download File]
Pollitz, F.F., Body-wave traveltime and amplitude shifts from asymptotic travelling-wave coupling, Geophys. J. Int., 167, 705-736 (2006). [Download File]
Pollitz, F.F., A new class of earthquake observations, Science, 313, 619-620 (2006). [Download File]
Pollitz, F.F., Nyst, M., Nishimura, T., and Thatcher, W., Inference of postseismic deformation mechanisms of the 1923 Kanto earthquake, Japan, J. Geophys. Res., 111, B0548, doi:10.1029/2005JB003901 (2006). [Download File]
Pollitz, F.F. and Vergnolle, M., Mechanical deformation model of the western U.S. instantaneous velocity field, Geophys. J. Int., 167, 421-444 (2006). [Download File]
Pollitz, F.F., Banerjee, P., and Burgmann, R., Postseismic relaxation following the great 2004 Sumatra-Andaman earthquake on a compressible self-gravitating Earth, Geophys. J. Int., 167, 397-420 (2006).[Download File]
Pollitz, F.F., Banerjee, P., Burgmann, R., Hashimoto, M., and Choosakul, N., Stress changes along the Sunda trench following the 26 December 2004 Sumatra-Andaman and 28 March 2005 Nias earthquakes, Geophys. Res. Lett., 33, L06309, 10.1029/2005GL02455 (2006). (2006). [Download File]
Nyst, M., Nishimura, T., Hamada, N., Pollitz, F.F., and Thatcher, W., The 1923 Kanto earthquake re-evaluated using a newly augmented geodetic data set, J. Geophys. Res., 111, B11306 (2006). [Download File]
Pollitz, F.F. and Fletcher, J.P., Waveform tomography of crustal structure in the South San Francisco Bay region, J. Geophys. Res., B08308, doi:10.1029/2005JB003509 (2005).
Pollitz, F.F., Nyst, M., Nishimura, T., and Thatcher, W., Coseismic slip distribution of the1923 Kanto earthquake, Japan, J. Geophys. Res., 100, B11408, doi:10.1029/2005JB003638 (2005). [Download File]
Arnadottir, T., Jonsson,S., Pollitz, F.F., Jiang, W., and Feigl, K., Post-seismic deformation following the June 2000 earthquake sequence in the south Iceland seismic zone, J. Geophys. Res., 110, B12308, doi:10.1029/2005JB003701 (2005). [Download File]
Pollitz, F.F., Transient rheology of the upper mantle beneath central Alaska inferred from the crustal velocity field following the 2002 Denali earthquake, J. Geophys. Res., B08407, doi:10.1029/2005JB003672 (2005). [Download File]
Banerjee, P., Pollitz, F.F., and Burgmann, R., Size and duration of the great 2004 Sumatra-Andaman earthquake from far-field static offsets, Science, 308, 1769-1772 (2005). [Download File]
Pollitz, F.F., and Nyst, M.C.J., A physical model for strain accumulation in the San Francisco Bay region, Geophys. J. Int., 160, 302-317 (2005). [Download File]
Pollitz, F.F., Bakun, W., and Nyst, M.C.J., A physical model for strain accumulation in the San Francisco Bay region, II: Stress evolution since 1838, J. Geophys. Res, 109, B11408, doi:10.1029/2004JB003003 (2004). [Download File]
Thomas, C., Livermore, R.A., and Pollitz, F.F., Motion of the Scotia Sea Plates, Geophys. J. Int., 155, 789-804 (2003).
Vergnolle, M., Pollitz, F.F., and Calais, E., Constraints on the viscosity of the continental crust and mantle from GPS measurements and postseismic deformation models in Western Mongolia, J. Geophys. Res., 108, 2502, doi:10.1029/2002JB002374 (2003). [Download File]
Pollitz, F.F., Vergnolle, M., and Calais, E., Fault interaction and stress triggering of 20th century earthquakes in Mongolia, J. Geophys. Res. 108, 2503, doi:10.1029/2002JB002375 (2003). [Download File]
Pollitz, F.F., Transient rheology of the uppermost mantle beneath the Mojave Desert, California, Earth Planet. Sci. Lett., 215, 89-104 (2003). [Download File]
Pollitz, F.F., Postseismic relaxation theory on a laterally heterogeneous viscoelastic model, Geophys. J. Int., 155, 57-78 (2003). [Download File]
Pollitz, F.F., The relationship between the instantaneous velocity field and the rate of moment release in the lithosphere, Geophys. J. Int., 153, 595-608 (2003). [Download File]
Hill, D.P., Pollitz, F.F., and Newhall, C., Earthquake-volcano interactions, Physics Today, 55, 41-47 (2002) [Download File]
Pollitz, F.F. and Sacks, I.S., Stress triggering of the 1999 Hector Mine earthquake by transient deformation following the 1992 Landers earthquake, Bull. Seismol. Soc. Am., 92, 1487-1496 (2002).[Download File]
Pollitz, F.F., Kellogg, L., and Bürgmann, R., Sinking mafic body in a reactivated lower crust: A mechanism for stress concentration at the New Madrid Seismic Zone, Bull. Seismol. Soc. Am., 91, 1882-1897 (2001). [Download File]
Pollitz, F.F., Wicks, C., and Thatcher, W., Mantle flow beneath a continental strike-slip fault: Postseismic deformation after the 1999 Hector Mine earthquake, Science, 293, 1814-1818 (2001). [Download File]
Pollitz, F.F., Viscoelastic shear zone model of a strike-slip earthquake cycle, J. Geophys. Res., 106, 26,541-26,560 (2001). [Download File]
Pollitz, F.F., Peltzer, G., and Bürgmann, R., Mobility of continental mantle: Evidence from postseismic geodetic observations following the 1992 Landers earthquake, J. Geophys. Res., 105, 8035-8054 (2000). [Download File]
Pollitz, F.F., Bürgmann, R., and Segall, P., Joint estimation of afterslip rate and postseismic relaxation following the 1989 Loma Prieta earthquake, J. Geophys. Res., 103, 26975-26992 (1998). [Download File]
Pollitz, F.F., Bürgmann, R., and Romanowicz, B., Viscosity of oceanic asthenosphere inferred from remote triggering of earthquakes, Science, 280, 1245-1249 (1998). [Download File]
Science and Products
Year Published: 2017
Shallow microearthquakes near Chongqing, China triggered by the Rayleigh waves of the 2015 M7.8 Gorkha, Nepal earthquake
We present a case of remotely triggered seismicity in Southwest China by the 2015/04/25 M7.8 Gorkha, Nepal earthquake. A local magnitude ML3.8 event occurred near the Qijiang district south of Chongqing city approximately 12 min after the Gorkha mainshock. Within 30km of this ML3.8 event there are 62 earthquakes since 2009 and only 7 ML>3events...
Han, Libo; Peng, Zhigang; Johnson, Christopher W.; Pollitz, Fred; Li, Lu; Wang, Baoshan; Wu, Jing; Li, Qiang; Wei, HongmeiView Citation
Han, L., Peng, Z., Johnson, C. W., Pollitz, F. F., Li, L., Wang, B., Wu, J., Qiang, L., and Wei, H., Shallow microearthquakes near Chongqing, China triggered by the Rayleigh waves of the 2015 M7.8 Gorkha, Nepal earthquake, Earth Planet. Sci. Lett.,
Year Published: 2017
Proceedings of the 11th United States-Japan natural resources panel for earthquake research, Napa Valley, California, November 16–18, 2016
The UJNR Panel on Earthquake Research promotes advanced research toward a more fundamental understanding of the earthquake process and hazard estimation. The Eleventh Joint meeting was extremely beneficial in furthering cooperation and deepening understanding of problems common to both Japan and the United States.The meeting included productive...
Detweiler, Shane; Pollitz, FredView Citation
Detweiler, S., and Pollitz, F., eds., 2017, Proceedings of the 11th United States-Japan natural resources panel for earthquake research, Napa Valley, California, November 16–18, 2016: U.S. Geological Survey Open-File Report 2017–1133, 147 p., https://doi.org/10.3133/ofr20171133.
Year Published: 2017
Viscoelastic lower crust and mantle relaxation following the 14–16 April 2016 Kumamoto, Japan, earthquake sequence
The 2016 Kumamoto, Japan, earthquake sequence, culminating in the Mw=7.0 16 April 2016 main shock, occurred within an active tectonic belt of central Kyushu. GPS data from GEONET reveal transient crustal motions from several millimeters per year up to ∼3 cm/yr during the first 8.5 months following the sequence. The spatial pattern...
Pollitz, Fred; Kobayashi, Tomokazu; Yarai, Hiroshi; Shibazaki, Bunichiro; Matsumoto, TakumiView Citation
Pollitz, F. F.; Kobayashi, T.; Yarai, H.; Shibazaki, B.; Matsumoto, T., Viscoelastic lower crust and mantle relaxation following the 14–16 April 2016 Kumamoto, Japan, earthquake sequence, Geophysical Research Letters, 44, 8795-8803 (2017)
Year Published: 2017
Connecting crustal seismicity and earthquake-driven stress evolution in Southern California
Tectonic stress in the crust evolves during a seismic cycle, with slow stress accumulation over interseismic periods, episodic stress steps at the time of earthquakes, and transient stress readjustment during a postseismic period that may last months to years. Static stress transfer to surrounding faults has been well documented to alter regional...
Pollitz, Fred; Cattania, CamillaView Citation
Pollitz, F.F. and Cattania, C., Connecting crustal seismicity and earthquake-driven stress evolution in southern California, J. Geophys. Res. Solid Earth, 122, 6473–6490, doi:10.1002/2017JB014200 (2017)
Year Published: 2017
A note on adding viscoelasticity to earthquake simulators
Here, I describe how time‐dependent quasi‐static stress transfer can be implemented in an earthquake simulator code that is used to generate long synthetic seismicity catalogs. Most existing seismicity simulators use precomputed static stress interaction coefficients to rapidly implement static stress transfer in fault networks with typically tens...
Pollitz, Fred
Year Published: 2017
Geodetic slip model of the 3 September 2016 Mw 5.8 Pawnee, Oklahoma, earthquake: Evidence for fault‐zone collapse
The 3 September 2016 Mw 5.8 Pawnee earthquake in northern Oklahoma is the largest earthquake ever recorded in Oklahoma. The coseismic deformation was measured with both Interferometric Synthetic Aperture Radar and Global Positioning System (GPS), with measureable signals of order 1 cm and 1 mm, respectively. We derive a...
Pollitz, Fred; Wicks, Charles W.; Schoenball, Martin; Ellsworth, William L.; Murray, MarkView Citation
Pollitz, F.F., Wicks, C., Schoenball, M., Ellsworth, W., and Murray, M., Geodetic slip model of the M5.8 3 September, 2016 Pawnee, Oklahoma, earthquake: Evidence for fault zone collapse, Seismol. Res. Lett., 88, DOI: 10.1785/0220170002, 2017.
Year Published: 2017
Implications of the earthquake cycle for inferring fault locking on the Cascadia megathrust
GPS velocity fields in the Western US have been interpreted with various physical models of the lithosphere-asthenosphere system: (1) time-independent block models; (2) time-dependent viscoelastic-cycle models, where deformation is driven by viscoelastic relaxation of the lower crust and upper mantle from past faulting events; (3) viscoelastic...
Pollitz, Fred; Evans, EileenView Citation
F. F. Pollitz, E. L. Evans; Implications of the earthquake cycle for inferring fault locking on the Cascadia megathrust. Geophys J Int 2017 ggx009. doi: 10.1093/gji/ggx009
Year Published: 2016
Persistent slip rate discrepancies in the eastern California (USA) shear zone
Understanding fault slip rates in the eastern California shear zone (ECSZ) using GPS geodesy is complicated by potentially overlapping strain signals due to many sub-parallel strike-slip faults and by inconsistencies with geologic slip rates. The role of fault system geometry in describing ECSZ deformation may be investigated with total variation...
Evans, Eileen; Thatcher, Wayne R.; Pollitz, Fred; Murray, Jessica R.
Year Published: 2016
The Earthquake‐Source Inversion Validation (SIV) Project
Finite‐fault earthquake source inversions infer the (time‐dependent) displacement on the rupture surface from geophysical data. The resulting earthquake source models document the complexity of the rupture process. However, multiple source models for the same earthquake, obtained by different research teams, often exhibit remarkable...
Mai, P. Martin; Schorlemmer, Danijel; Page, Morgan T.; Ampuero, Jean-Paul; Asano, Kimiyuki; Causse, Mathieu; Custodio, Susana; Fan, Wenyuan; Festa, Gaetano; Galis, Martin; Gallovic, Frantisek; Imperatori, Walter; Käser, Martin; Malytskyy, Dmytro; Okuwaki, Ryo; Pollitz, Fred; Passone, Luca; Razafindrakoto, Hoby N. T.; Sekiguchi, Haruko; Song, Seok Goo; Somala, Surendra N.; Thingbaijam, Kiran K. S.; Twardzik, Cedric; van Driel, Martin; Vyas, Jagdish C.; Wang, Rongjiang; Yagi, Yuji; Zielke, OlafView Citation
Mai, P. Martin, Danijel Schorlemmer, Morgan Page, Jean-Paul Ampuero, Kimiyuki Asano, Mathieu Causse, Susana Custodio, Wenyuan Fan, Gaetano Festa, Martin Galis, Frantisek Gallovic, Walter Imperatori, Martin Käser, Dmytro Malytskyy, Ryo Okuwaki, Fred Pollitz, Hoby Razafindrakoto, Haruko Sekiguchi, Seok-Goo Song, Surendra Somala, Kiran Thingbaijam, Cedric Twardzik, Martin van Driel, Jagdish Vyas, Rongjiang Wang, Yuji Yagi, and Olaf Zielke, 2016, The Earthquake-Source Inversion Validation (SIV) Project: Seismological Research Letters, v. 87, p. 690-708, doi:10.1785/0220150231
Year Published: 2016
Postseismic gravity change after the 2006–2007 great earthquake doublet and constraints on the asthenosphere structure in the central Kuril Islands
Large earthquakes often trigger viscoelastic adjustment for years to decades depending on the rheological properties and the nature and spatial extent of coseismic stress. The 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands resulted in significant postseismic gravity change in Gravity Recovery and Climate...
Han, Shin-Chan; Sauber, Jeanne; Pollitz, Fred
Year Published: 2016
Lithospheric rheology constrained from twenty-five years of postseismic deformation following the 1989 Mw 6.9 Loma Prieta earthquake
The October 17, 1989 Mw 6.9 Loma Prieta earthquake provides the first opportunity of probing the crustal and upper mantle rheology in the San Francisco Bay Area since the 1906 Mw 7.9 San Francisco earthquake. Here we use geodetic observations including GPS and InSAR to characterize the Loma Prieta earthquake postseismic displacements from 1989 to...
Huang, Mong-Han; Burgmann, Roland; Pollitz, FredView Citation
Mong-Han Huang, Roland Bürgmann, Fred Pollitz, Lithospheric rheology constrained from twenty-five years of postseismic deformation following the 1989 Mw 6.9 Loma Prieta earthquake, Earth and Planetary Science Letters, Volume 435, 1 February 2016, Pages 147-158, ISSN 0012-821X, https://doi.org/10.1016/j.epsl.2015.12.018.
Year Published: 2016
Seismic velocity structure of the crust and shallow mantle of the Central and Eastern United States by seismic surface wave imaging
Seismic surface waves from the Transportable Array of EarthScope's USArray are used to estimate phase velocity structure of 18 to 125 s Rayleigh waves, then inverted to obtain three-dimensional crust and upper mantle structure of the Central and Eastern United States (CEUS) down to ∼200 km. The obtained lithosphere structure confirms...
Pollitz, Fred; Mooney, Walter D.View Citation
Pollitz, F. F. and Mooney, W. D., Seismic velocity structure of the crust and shallow mantle of the Central and Eastern United States by seismic surface wave imaging, Geophys. Res. Lett., 42, 1-9, doi:10.1002/2015GL066637 (2016).
Pre-USGS Publications
Date published: March 7, 2019
STATIC1D
These programs solve the equations of static equilibrium in a spherically layered isotropic medium using a decomposition into spheroidal and toroidal motions.
Attribution: Earthquake Hazards Program
Date published: March 6, 2019
Direct Green's Function Synthetic Seismograms
These programs are an implementation of the Direct Green’s Function method described by Friederich and Dalkolmo (1995) and Dalkolmo (1993).
Attribution: Earthquake Hazards Program
Date published: January 29, 2007
VISCO1D
VISCO1D-v3 is a program package to calculate quasi-static deformation on a layered spherical Earth from a specified input source (fault plane parameters) at specified points on the surface or at depth.
Attribution: Earthquake Hazards Program