Receiver static corrections from passive seismic data
, by Steve Cole
A stack power optimization method is used to compute receive station statics using data
from a passive seismic survey. The method relies on the presence of vertically incident
plane wave energy in the data. The computed statics are those time shifts that would best
align such vertically incident events. Two problems that affect this algorithm are the
effect of random noise (and coherent but not vertically incident energy) on the cross-
correlation procedure that is central to the processing, and the liability to distinguish
between true statics and arrival time differences caused by energy that is not vertically
incident. Using more data in the crosscorrelation helps to overcome the noise problem
somewhat. To determine the effectiveness of the method, I process passive data recorded
during two different recording periods independently. The results show that there is some
agreement between the two statics solutions obtained, but not enough that either the problem
of interfering noise or of non-vertical incidence is completely overcome. The results
suggest that multichannel filtering to enhance vertically incident energy relative to the
incoherent and coherent noise is necessary if the method is to be able to "see" through the
noise better.
STANFORD