Fig. 2.(a) The Parkfield recurrences1 represents the failure stress of the fault. Most
characteristic earthquakes occur at s1; the 1934 shock occurred at s2. A constant loading rate of 2.8 cm per year and a
coseismic slip of 60 cm for the Parkfield earthquake sequences in 1881,
1901,1922,1934, and 1966 are assumed (56). (b) Series of earthquake
sequences at Parkfield since 1850 [after (5)], The line represents the
linear regression of the time of the sequence obtained without the 1934
sequence, The anticipated time of the seventh (that is, the next)
Parkfield sequence for the regression is January 1988. (c) Shocks of
ML greater than 4 since 1930 have tended to occur when the
stress exceeds s2 .
