Design and Processing Considerations For a Passive Seismic Survey
, by Steve Cole
Passive seismology is seismology without the use of a
controlled source to send sound waves into the earth.
Interest in passive seismology originally grew out of the desire to
detect and locate earthquakes and underground nuclear blasts.
Teleseismic events contain information about the geology
in the vicinity of the receivers, since the teleseismic
energy will reflect, refract, and diffract off structures beneath
the recording location. Microseismic activity near the
recording location will provide energy that may be useful as well.
Signal to noise ratios are typically small compared to controlled-source
surveys, so sophisticated processing techniques are needed to overcome
noise contamination and image the subsurface structures.
This paper is a brief review of field and processing
techniques that have been used in passive seismic experiments to date.
Also included are some thoughts on how past work needs to
be supplemented to meet the particular requirements of
exploration seismology.