A single‐station fault‐Plane solution method

Body wave forms contain a wealth of information on the nature of the seismic source which generated them. In the case of a shallow earthquake, the interference of direct waves and surface reflections can be advantageously used in finding standard orientation parameters by modeling the shape and amplitude of the wave form. This paper examines the assertion that a single, three‐component, long‐period station can be used to find fault‐plane solutions by using both P and S wave amplitudes and interpreting the shape of the waveform. This assertion is tested using the Santa Barbara earthquake (mb = 5.3, SCP) of August 13, 1978, for which there is a fault‐plane solution from local data. Using a simple method of calculating amplitudes from the shape of observed P and SH pulses recorded at SCP (State College, PA), it is shown that the type of mechanism can easily be found (e.g. thrust vs strike‐slip) and, surprisingly, that there is general agreement with the local solution. © 1979 by the Chinese Geophysical Societ