U.S. Geological Survey: Karen Felzer

Karen Felzer

Karen Felzer is a research scientist on the Earthquake Hazards team. Her direct supervisor is Dr. Ned Field. Her research involves using statistical techniques to study earthquakes, with a focus on earthquake interaction. This has included work on long distance triggering of aftershocks by small earthquakes, stress shadows (or the lack thereof), foreshocks, multiplets, and secondary aftershocks. Karen has also worked with the Working Group on California Earthquake Probabilities.

Free computer programs for download

NEW!!! Stochastic/ETAS aftershock and earthquake catalog simulation program for matlab users!
Go to the download page Here

Papers and Abstracts

Submitted and In Press

Felzer, Karen R. and Debi Kilb, Is the footprint of an aftershock sequence larger than we think: A new view from the well recorded aftershocks of the 2001 and 2005 magnitude ~5 Anza, California earthquakes, Bull. Seis. Soc. Am., submitted, 2008.
document in pdf

Felzer, Karen R., Simulated aftershock sequences for a M 7.8 earthquake on the Southern San Andreas Fault, Seism. Res. Lett., in press, 2008.
document in Word format

Publications

Gomberg, J. and K. Felzer, A model of earthquake triggering probabilities and application to dynamic deformations constrained by ground motion observations, J. Geophys. Res., 113, B10317, doi:10.1029/2007JB005184, 2008.
manuscript in pdf

Hardebeck, J. L., K. R. Felzer, and A. J. Michael, Improved test results reveal that the accelerating moment release hypothesis is statistically insignificant, J. Geophys. Res., 113, B08310, doi:10.1029/2007JB005410, 2008.
manuscript in pdf

Felzer, K. R. and Cao, Tianqing, WGCEP Historical California earthuake catalog, Appendix H in The Uniform California Earthquake Rupture Forecast, version 2 (UCERF 2): U.S. Geological Survey Open-File Report 2007-1437H and California Geological Survey Special Report 203H, 127 pp., 2008.
document in pdf
WGCEP Appendix H California Region 1850-2006 Catalog in ascii format

Felzer, K. R., Calculating California seismicity rates, Appendix I in The Uniform California Earthquake Rupture Foreast, version 2 (UCERF 2): U.S. Geological Survey Open-File Report 2007-1437I and California Geological Survey Special Report 203I, 42 pp., 2008.
document in pdf

Felzer, K. R., Empirical estimation of regional time variation in seismicity rates, Appendix M in The Uniform California Earthquake Rupture Forecast, version 2 (UCERF 2): U.S. Geological Survey Open-File Report 2007-1437M and California Geological Survey Special Report 203M, 19 pp., 2008.
document in pdf

Felzer, K. R. and E. E. Brodsky, Decay of aftershock density with distance indicates triggering by dynamic stress, Nature , 441, 735-738, 2006.
Self-formatted copies of the paper
article in pdf
Supplementary Figures

If you have a personal or institutional subscription to Nature you can access the published version of the paper here

Felzer, K. R., and E. E. Brodsky, Testing the stress shadow hypothesis, Journal of Geophysical Research, 110, B05S09, doi:1029/2004JB003277, 2005.
abstract in html
article in pdf

Felzer, K. R., R. E. Abercrombie, and G. Ekström, A Common Origin for Aftershocks, Foreshocks, and Multiplets, Bull. Seis. Soc. Am. , 94, 88-99, 2004.
abstract in html
article in pdf

Felzer, K. R., R. E. Abercrombie, and G. Ekström, Secondary aftershocks and their importance for aftershock prediction, Bull. Seis. Soc. Am., 93, 1433-1448, 2003.
abstract in html
article in pdf

Felzer, K. R., T. W. Becker, R. E. Abercrombie, G. Ekström, and J. R. Rice, Triggering of the 1999 Mw 7.1 Hector Mine earthquake by aftershocks of the 1992 Mw 7.3 Landers earthquake, J. Geophys. Res., 107, 2190, doi:10.1029/2001JB000911, 2002.
abstract in html
article in pdf

Abercrombie, R. E., Antolik, M. A., Felzer, K. R., and G. Ekström, G., The 1994 Java earthquake: slip over a subducting seamount, J. Geophys. Res., 106, 6595-6608, 2001. abstract

Felzer, K. R., and G. C. Beroza, Deep Structure of a fault discontinuity, Geophysical Res. Letters, 26, 2121-2124, 1999. web link

Conference Abstracts

Click here for a list and links

Online Talks

SCEHAP Conference, 2007:
Universality of the Gutenberg-Richter Relationship

CalTech SeismoLab Seminar, January 2007:
The Wonderful World of Aftershocks

American Geophysical Union Meeting 2006:
Calculating the Gutenberg-Richter b Value

American Geophysical Union Meeting 2005:
Stress Change Amplitude Does Not Affect Aftershock Timing

Seismological Society of America Meeting 2005:
Decay rate of aftershock density with distance from the mainshock
Covers observations and physical implications of aftershock spatial decay

American Geophysical Union Fall Meeting, 2002:
"A Common Origin for Aftershocks, Foreshocks, and Multiplets"

Teaching Experience

Lecturer for summer school at UCLA: ESS 8, Earthquakes Course website

Grad School Teaching Experience
Fall 2001 Head Teaching Fellow for Professor Göran Ekström for Science A43, Environmental Risks and Disasters .
Fall 2000 Teaching Fellow for Science A43
Fall 1999 Teaching Fellow for Science A43
Spring 1999 Teaching Fellow for Earth and Planetary Sciences 6: Introduction to Environmental Science: The Solid Earth, with Professor Göran Ekström

Resources for students

office phone: 626-583-7822

U. S. Geological Survey, 525 S. Wilson, Pasadena, CA 91106

Work in progress items, for pick-up by co-authors only!! thank you!