Premium
Post‐seismic slip on the San Andreas Fault at the northwestern end of the 1989 Loma Prieta Earthquake rupture zone
Author(s) -
Langbein John O.
Publication year - 1990
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl017i008p01223
Subject(s) - seismology , geology , aftershock , slip (aerodynamics) , san andreas fault , episodic tremor and slip , foreshock , fault plane , seismic gap , earthquake rupture , fault (geology) , subduction , tectonics , physics , thermodynamics
A small geodetic network spanning the San Andreas fault was measured 7, 77, 157, and 200 days following the October 17, 1989 Loma Prieta M 7.1 earthquake. This network is located at the northwestern end of the rupture plane defined by the locations of numerous aftershocks. In the initial 70‐day interval, the measured line‐length changes revealed that 5.4 ± 0.4 mm of right‐lateral slip occurred within the network. However, during the later 4 month interval only a marginally significant rate, 3.2 ± 1.4 mm/yr, of right‐lateral slip could be detected. Thus, it appears that the measured slip is a typical response of the fault following a major shock in that the rate of slip decreases rapidly with time. However, the magnitude of the post‐seismic slip is less than 0.5% of the inferred co‐seismic slip at depth.