Summary: | This report presents the results of a feasibility study designed to assess whether microseismic location techniques can provide enough accuracy and precision to enable a
high resolution study of the spatial distribution of microseismic events induced during
a hydraulic fracture experiment. We calculated the 90% confidence regions for six synthetic microevent 'clusters' along the azimuth of a hydraulic fracture produced during
Atlantic Richfield's 1993 Fracture Technology Field Demonstration Project in Jasper,
Texas. Examination of the confidence regions for the absolute locations indicates that
microseismic events can be confidently located for areas near the monitoring wells but
away from the plane intersecting the two observation points. We determined that the
resolution for events located at the ends of the fracture is poor but improves dramatically nearer the wells. The minimum dimensions of the 90% confidence regions for events within our study area are approximately 8 ft in the northwest-southeast direction, 3 ft in the northeast-southwest direction, and 3 ft in depth.
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