Due to a lapse in appropriations, the majority of USGS websites may not be up to date and may not reflect current conditions. Websites displaying real-time data, such as Earthquake and Water and information needed for public health and safety will be updated with limited support. Additionally, USGS will not be able to respond to inquiries until appropriations are enacted.  For more information, please see www.doi.gov/shutdown

Jeanne Hardebeck



- Ph.D. Geophysics, California Institute of Technology, 2001.

- M.S. Geophysics, California Institute of Technology, 1997.

- A.B. Computer Science, Cornell University, 1993.



- Research Geophysicist, USGS Earthquake Hazards Team, 2004-present.

- Mendenhall Postdoctoral Scholar, USGS Earthquake Hazards Team, 2003-2004.

- Green Postdoctoral Scholar, Scripps Institution of Oceanography, U.C. San Diego, 2000-2003.

- Graduate Research Assistant, California Institute of Technology, 1994-2000.



- Presidential Early Career Award for Scientists and Engineers (PECASE), 2009. 

- James B. Macelwane Medal, American Geophysical Union, 2007.

- Charles F. Richter Early Career Award, Seismological Society of America, 2006.


Research Interests

- Crustal stress and the strength of faults.

- Earthquake statistics and testing earthquake forecasting methods.

- California stress field and seismotectonics.

- Earthquake triggering and effects on probabilistic seismic hazard assessment.















Hardebeck, J. L., (2012), Coseismic and Postseismic Stress Rotations due to Great Subduction Zone Earthquakes, Geophys. Res. Lett. 39, L21313, doi:10.1029/2012GL053438.   [link to journal article]


Tormann, T., S. Wiemer, and J. L. Hardebeck, (2012), Earthquake Recurrence Models Fail when Earthquakes Fail to Reset the Stress Field, Geophys. Res. Lett. 39, L18310, doi:10.1029/2012GL052913.  [link to journal article]


Hardebeck, J.L. (2012), Fluid-Driven Seismicity Response of the Rinconada Fault near Paso Robles, California, to the 2003 M 6.5 San Simeon Earthquake, Bull. Seism. Soc. Am., 102, 377-390. [link to journal article]


Hardebeck, J. (2010), Aftershocks are well aligned with the background stress field, contradicting the hypothesis of highly heterogeneous crustal stress, J. Geophys. Res., 115, B12308, doi:10.1029/2010JB007586.   [link to journal article]



 Hardebeck, J. L., Seismotectonics and Fault Structure of the California Central Coast, Bull. Seism. Soc. Am., 100, 1031-1050, 2010.  [link to journal article]



Shelly, D. R. and J. L. Hardebeck, Precise tremor source locations and amplitude variations along the lower-crustal central San Andreas Fault, Geophys. Res. Lett., 37, L14301, doi:10.1029/2010GL043672, 2010.  [link to journal article]


Lin, G., C. H. Thurber, H. Zhang, E. Hauksson, P. M. Shearer, F. Waldhauser, T. M. Brocher, J. Hardebeck, A California Statewide Three-Dimensional Seismic Velocity Model from Both Absolute and Differential Time, Bull. Seism. Soc. Am., 100, 225-240, 2010.  [link to journal article]


Hardebeck, J. L., A. Aron, Earthquake Stress Drops and Inferred Fault Strength on the Hayward Fault, East San Francisco Bay, California, Bull. Seism. Soc. Am., 99, 1801-1814, 2009. [link to journal article]


Aron, A., and J. L. Hardebeck, Seismicity Rate Changes along the Central California Coast due to Coulomb Stress Changes from the 2003 M6.5 San Simeon and 2004 M6.0 Parkfield Earthquakes, Bull. Seism. Soc. Am., 99, 2280-2292, 2009. [link to journal article]


Hardebeck, J. L., K. R. Felzer, A. J. Michael, Improved Tests Reveal that the Accelerating Moment Release Hypothesis is Statistically Insignificant, J. Geophys. Res., 113, B08310, doi:10.1029/2007JB005410, 2008.  [link to journal article]


McLaren, M. K., J. L. Hardebeck, N. van der Elst, J. Unruh, G. W. Bawden, J. L. Blair, Complex faulting associated with the 22 December 2003 Mw6.5 San Simeon, California earthquake, aftershocks and postseismic deformation, Bull. Seism. Soc. Am., 98, 1659-1680, 2008.  [link to journal article]


Boyd, O. S., F. Pollitz, Y. Zeng, J. L. Hardebeck, C. G. Bufe, R. L. Wesson, Towards a time-dependent probabilistic seismic hazard analysis for Alaska, in J. T. Freymueller, P. J. Haeussler, R. L. Wesson, and G. Ekström, eds., Active Tectonics and Seismic Potential of Alaska, Geophysical Monograph 179, American Geophysical Union, Washington, D.C., pp. 399-416, 2008.


Hardebeck, J. L., A. J. Michael, T. M. Brocher, Seismic Velocity Structure and Seismotectonics of the Eastern San Francisco Bay Region, California, Bull. Seism. Soc. Am., 97, 826-842, 2007.  [link to journal article]


Hardebeck, J. L., Homogeneity of Small-Scale Earthquake Faulting, Stress and Fault Strength, Bull. Seism. Soc. Am., 96, 1675-1688, 2006.  [link to journal article]


Hardebeck, J. L. and A. J. Michael, Damped Regional-Scale Stress Inversions: Methodology and Examples for Southern California and the Coalinga Aftershock Sequence, J. Geophys. Res., 111, B11310, doi:10.1029/2005JB004144, 2006.  [link to journal article]


Thurber, C., H. Zhang, F. Waldhauser, J. Hardebeck, A. Michael, D. Eberhart-Phillips, Three-Dimensional Compressional Wavespeed Model, Earthquake Relocations, and Focal Mechanisms for the Parkfield, California, Region, Bull. Seism. Soc. Am., 96, S38-S49, 2006. [link to journal article]


Kilb, D. and J. L. Hardebeck, Fault Parameter Constraints Using Relocated Earthquakes: A Validation of First Motion Focal Mechanism Data, Bull. Seism. Soc. Am., 96, 1140-1158, 2006.  [link to journal article]


Bakun, W. H., B. Aagaard, B. Dost, W. L. Ellsworth, J. L. Hardebeck, R. A. Harris, C. Ji, M. J. S. Johnston, J. Langbein, J. J. Lienkaemper, A. J. Michael, J. R. Murray, R. M. Nadeau, P. A. Reasenberg, M. S. Reichle, E. A. Roeloffs, A. Shakal, R. W. Simpson and F. Waldhauser, Implications for prediction and hazard assessment from the 2004 Parkfield earthquake, Nature 437, 969-974, 2005.  [link to journal article]


Langbein, J., D. Dreger, J. Fletcher, J. L. Hardebeck, M. Hellweg, C. Ji, M. Johnston, J. R. Murray, R. Nadeau, M. J. Rymer, J. A. Treiman, Preliminary Report on the 28 September 2004, M 6.0 Parkfield, California Earthquake, Seism. Res. Lett., 76, 10-26, 2005.


Becker, T. W., J. L. Hardebeck, G. Anderson, Constraints on fault slip rates of the southern California plate boundary from GPS velocity and stress inversions, Geophys. J. Int., doi:10.1111/j.1365-246X.2004.02528.x, 2004.


Hardebeck, J. L., and A. J. Michael, Stress orientations at intermediate angles to the San Andreas Fault, California, J. Geophys. Res., 109, B11303, doi:10.1029/2004JB003239, 2004.  [link to journal article]


Hardebeck, J. L., Stress Triggering and Earthquake Probability Estimates, J. Geophys. Res., 109, B04310, doi:10.1029/2003JB002437, 2004.  [link to journal article]


Hardebeck, J. L., J. Boatwright, D. Dreger, R. Goel, V. Graizer, K. Hudnut, C. Ji, L. Jones, J. Langbein, J. Lin, E. Roeloffs, R. Simpson, K. Stark, R. Stein, J. C. Tinsley, Preliminary Report on the 22 December 2003 M6.5 San Simeon, California, Earthquake, Seism. Res. Lett., 75, 155-172, 2004.


Hardebeck, J. L. and P. M. Shearer, Using S/P Amplitude Ratios to Constrain the Focal Mechanisms of Small Earthquakes, Bull. Seism. Soc. Am., 93, 2434-2444, 2003. [link to journal article]


Shearer, P. M., J. L. Hardebeck, L. Astiz, and K. B. Richards-Dinger, Analysis of similar event clusters in aftershocks of the 1994 Northridge, California, earthquake, J. Geophys. Res., 108, B1, DOI:10.1029/2001JB000685, 2003. [link to journal article]


Hardebeck, J. L. and P. M. Shearer, A new method for determining first-motion focal mechanisms, Bull. Seism. Soc. Am., 92, 2264-2276, 2002.  [link to journal article]


Hardebeck, J. L. and E. Hauksson, Crustal stress field in southern California and its implications for fault mechanics, J. Geophys. Res., 106, 21,859-21,882, 2001.  [link to journal article]


Hardebeck, J. L. and E. Hauksson, Stress orientations obtained from earthquake focal mechanisms: What are appropriate uncertainty estimates?, Bull. Seism. Soc. Am., 91, 250-262, 2001.  [link to journal article]


Scientists from the U.S. Geological Survey, Southern California Earthquake Center, and California Division of Mines and Geology, Preliminary Report on the 10/16/1999 M7.1 Hector Mine, California, Earthquake, Seism. Res. Lett., 71, 11-23, 2000.


Hardebeck, J. L. and E. Hauksson, Role of Fluids in Faulting Inferred from Stress Field Signatures, Science, 285, 236-239, 1999.  [link to journal article]


Hardebeck, J. L., J. J. Nazareth, and E. Hauksson, The static stress change triggering model: Constraints from two southern California aftershock sequences, J. Geophys. Res., 103, 24,427-24,438, 1998.  [link to journal article]


Gaina, C., R. D. Müller, J.-Y. Royer, J. Stock, J. Hardebeck and P. Symonds, The tectonic history of the Tasman Sea:  A puzzle with 13 pieces, J. Geophys. Res., 103, 12,413-12,433, 1998.


Hardebeck, J. L. and E. Hauksson, Static Stress Drop in the 1994 Northridge, California, Aftershock Sequence, Bull. Seism. Soc. Am., 87, 1495-1501, 1997.  [link to journal article]


Hardebeck, J. and D. L. Anderson, Eustasy as a Test of the Cretaceous Superplume Hypothesis, Earth Planet. Sci. Lett. 137, 101-108, 1996.