Experiments in Improving Earthquake Locations

We are applying a variety of new methods to improve earthquake locations in southern California and other regions in order to better delineate fault structures.

***NEW*** Get our latest relocated catalog for southern California, LSH_1.12, obtained using waveform cross-correlation, at: http://www.geology.wisc.edu/~glin/LSH/

Relocation methods and results are described in the following papers:

  • Shearer, P.M., Improving local earthquake locations using the L1-norm and waveform cross-correlation: Application to the Whittier Narrows, California, aftershock sequence, J. Geophys. Res., 102, 8269-8283, 1997. (PDF)
  • Shearer, P.M. and L. Astiz, Locating nuclear explosions using waveform cross-correlation, 19th Annual Seismic Research Symposium on Monitoring a Comprehensive Test Ban Treaty, Proceedings, 301-309, 1997. (PDF)
  • Shearer, P.M., Evidence for a fault at 18 km depth beneath Oak Ridge, southern California, from a cluster of small earthquakes, Bull. Seismol. So. Am., 88, 1327-1336, 1998.
  • Shaw, J.H. and P.M. Shearer, An elusive blind-thrust fault beneath metropolitan Los Angeles, Science, 283, 1516-1518, 1999. (PDF)
  • Astiz, L., P.M. Shearer and D.C. Agnew, Precise relocations and stress-change calculations for the Upland earthquake sequence in southern California, J. Geophys. Res., 105, 2937-2853, 2000. (PDF)
  • Astiz, L., and P.M. Shearer, Earthquake relocations in the inner Continental Borderland, offshore southern California, Bull. Seismol. Soc. Am., 90, 425-449, 2000. (PDF)
  • Richards-Dinger, K.B. and P.M. Shearer, Earthquake locations in southern California obtained using source specific station terms, J. Geophys. Res., 105, 10,939-10,960, 2000. (PDF)
  • Shearer, P.M., Improving global seismic event locations using source-receiver reciprocity, Bull. Seismol. Soc. Am., 91, 594-603, 2001. (PDF)
  • Shearer, P.M., Parallel fault strands at 9-km depth resolved on the Imperial Fault, Southern California, Geophys. Res. Lett., 29(14), doi: 10.1029/2002GL015302, 2002. (PDF)
  • 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), 2035, doi:10.1029/2001JB000685, 2003. (PDF)
  • Wolfe, C.J., P.G. Okubo and P.M. Shearer, Mantle fault zone beneath Kilauea volcano, Hawaii, Science, 300, 478-480, 2003. (PDF)
  • Wolfe, C.J., P.G. Okubo, G. Ekstrom, M. Nettles and P.M. Shearer, Characteristics of deep (>= 13 km) Hawaiian earthquakes and Hawaiian earthquakes west of 155.55W, Geochem. Geophys. Geosyst., 5, Q04006, doi:10.1029/2003GC000618, 2004. (PDF)
  • Grant, L.B. and P.M. Shearer, Activity of the offshore Newport-Inglewood Rose Canyon fault zone, coastal southern California, from relocated microseismicity, Bull. Seismol. Soc. Am., 94, 747-752, 2004. (PDF)
  • Konter J.G., H. Staudigel, S.R. Hart and P.M. Shearer, Seafloor seismic monitoring of an active submarine volcano: Local seismicity at Vailulu'u Seamount, Samoa, Geochem. Geophys. Geosyst., 5, Q06007, doi:10.1029/2004GC000702, 2004. (PDF)
  • Lin., G. and P. Shearer, Tests of relative earthquake location techniques using synthetic data, J. Geophys. Res., 110, B4, B04304, doi:10.1029/2004JB003380, 2005. (PDF)
  • Hauksson, E. and P. Shearer, Southern California hypocenter relocation with waveform cross-correlation, Part 1: Results using the double-difference method, Bull. Seismol. Soc. Am., 95, 896-903, doi:10.1785/0120040167, 2005.
  • Shearer, P., E. Hauksson and G. Lin, Southern California hypocenter relocation with waveform cross-correlation, Part 2: Results using source-specific station terms and cluster analysis, Bull. Seismol. Soc. Am., 95, 904-915, doi:10.1785/0120040168, 2005.
  • Lin, G., P. Shearer and Y. Fialko, Obtaining absolute locations for quarry seismicity using remote sensing data, Bull. Seismol. Soc. Am., 96, 722-728, doi: 10.1785/0120050146, 2006.
  • Lin, G., and P. Shearer, The COMPLOC earthquake location package, Seismol. Res. Lett., 77, 440-444, 2006.
  • Cochran, E.S., and P.M. Shearer, Infrasound events detected with the Southern California Seismic Network, Geophys. Res. Lett., 33, L19803, doi:10.1029/2006GL026951, 2006.
  • Guzofski, C.A., J.H. Shaw, G. Lin, and P.M. Shearer, Seismically active wedge structure beneath the Coalinga anticline, San Joaquin basin, California, J. Geophys. Res., 112, B3, B03S05, doi: 10.1029/2006JB004465, 2007.
  • Lin, G., and P. Shearer, Estimating local Vp/Vs ratios within similar event clusters, Bull. Seismol. Soc. Am., 97, 379-388, doi: 10.1785/0120060115, 2007.
  • Lin, G., P.M. Shearer, E. Hauksson, and C.H. Thurber, A three-dimensional crustal seismic velocity model for southern California from a composite event method, J. Geophys. Res., 112, B11306, doi: 10.1029/2007JB004977, 2007.
  • Lin, G., P.M. Shearer, and E. Hauksson, Applying a three-dimensional velocity model, waveform cross correlation, and cluster analysis to locate southern California seismicity from 1981 to 2005, J. Geophys. Res., 112, B12309, doi: 10.1029/2007JB004986, 2007.