Microseismic multiplet has been used to estimate detailed structures of deep reservoir at Soultz HDR field, France. The multiplet is a group of microseismic events with similar waveforms in spite of different origin times. A hydraulic fracturing experiment was carried out at Soultz in 2000, and the artificial geothermal reservoir was created around the depth of 5,000 m. The induced microseismic events have been observed using downhole detectors, and more than 40,000 events have been triggered in our recording system. Precise source locations of induced microseismic multiplets have been estimated using the multiplet-clustering analysis, and seismically activated structural planes have been estimated as well as their orientations. The principal stress directions were also estimated based on the orientations and the estimated slip directions of structural planes. The results of analyses are demonstrated in this paper, and we discuss the feasibility of utilizing microseismic multiplets for evaluation of enhanced geothermal reservoir.

Press the Back button in your browser, or search again.

Copyright 2003, Stanford Geothermal Program: Readers who download papers from this site should honor the copyright of the original authors and may not copy or distribute the work further without the permission of the original publisher.