Conclusions

  • The relative amount of displacement on the Carrizo segment as opposed to the Cholame segment increases only slightly as a result of the increased fault depth (TCholame/TCarrizo=1)

  • As the strength of the Carrizo segment relative to that of Cholame increases, the segment boundary becomes more clearly defined by the change in surficial offset.

  • The model curves do not fit the offset data on the southeast end of the Carrizo segment because the San Andreas fault trace geometry changes as it enters the Big Bend (at approximately 100 km) and the loading geometry changes.

  • Because there is no prior rupture history known for the Cholame segment, it is difficult to separate out the effects of prior ruptures and loading from earthquakes on adjacent faults from the modeled contrast in fault segment strength.

  • Based on the data plotted on the model results, the data fits a stressdrop ratio between 2/3 and 1/3.



    • References

    Erikson, L. L, DIS3D: A three dimensional dislocation program with applications to faulting in the earth, unpublished Masters Thesis, Stanford University, Stanford, CA, 1987.

    Grant, L.B., and A. Donnellan, 1994, 1855 and 1991 surveys of the San Andreas Fault; implications for fault mechanics, Bulletin of the Seismological Society of America, 84 (2), pp. 241-246.

    Grant, L.B., and K.E. Sieh, 1994, Paleoseismic evidence of clustered earthquakes on the San Andreas Fault in the Carrizo Plain, California, Journal of Geophysical Research, 99, pp. 6819-6841.

    Jennings, C. W., Strand, R. G.; Rogers, T. H., Geologic map of California. Calif. Div. Mines and Geol., Sacramento, Calif., USA. 1977.

    Lienkaemper, J.J., and T.A. Sturm, 1989, Reconstruction of a channel offset in 1857(?) by the San Andreas Fault near Cholame, California, Bulletin of the Seismological Society of America, 79 (3), pp. 901-909. Sieh, K.E., 1978, Slip along the San Andreas fault associated with the great 1957 earthquake, Bulletin of the Seismological Society of America, 68, pp. 1421-1448.



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