Active faulting and deformation of the Coalinga anticline as interpreted from three-dimensional velocity structure and seismicity
This work gives a clear picture of the geometry of aftershock seismicity in a large thrust earthquake. Interpretation of hypocenters and fault plane solutions, from the 1983 Coalinga, Coast Range California, earthquake sequence, in combination with the three-dimensional velocity structure shows that the active faulting beneath the fold primarily consists of a set of southwest dipping thrusts uplifting blocks of higher-velocity material. With the three-dimensional velocity model each individual hypocenter moved slightly (0-2km) in accord with the details of the surrounding velocity structure, so that secondary features in the seismicity pattern are more detailed than with a local one-dimensional model and station corrections. The overall character of the fault plane solutions was not altered by the three-dimensional model, but the more accurate ray paths did result in distinct changes. In particular, the mainshock has a fault plane dipping 30?? southwest instead of the 23?? obtained with the one-dimensional model. -from Author
Citation Information
Publication Year | 1989 |
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Title | Active faulting and deformation of the Coalinga anticline as interpreted from three-dimensional velocity structure and seismicity |
Authors | D. Eberhart-Phillips |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Journal of Geophysical Research |
Index ID | 70015514 |
Record Source | USGS Publications Warehouse |