Strain Release in the Circum-Pacific Belt: Kern County 1952, Desert Hot Springs 1948, San Francisco 1957

Three Californian aftershock sequences are investigated with the purpose of checking the oscillation pattern of strain release between the two ends of the elongated aftershock zone, as found earlier for the Aleutian Islands 1957 aftershock sequence. In the Kern County 1952 sequence the oscillation pattern was verified not only for the White Wolf fault but also for a second fault, probably the Edison fault, which became active in the sequence. A model is presented, which embodies seismological as well as geological and geodetic statements given by different authors. Possible reasons are discussed for the absence of the oscillation pattern in the Desert Hot Springs 1948 sequence, whereas for the San Francisco 1957 sequence the oscillation pattern could be well asserted. Some inferences are drawn concerning the aftershock appearance in general.