Seismological Investigation of Crack Formation in Hydraulic Rock Fracturing Experiments and in Natural Geothermal Environments. Progress Report, September 1, 1981-August 31, 1982

摘要

Accomplishments during the present reporting period are: high-quality digital data obtained in the crater and the flank of Mt. St. Helens by the deployment of 9 event-recorders; discovery of striking differences in arrival times and amplitudes of seismic events between the crater station and flank stations; successful interpretation of the above observations by a powerful new method of seismogram synthesis called Gaussian Beam Method; evidence obtained at Mt. St. Helens for a close connection between the volcanic tremor and so-called long-period events; further development of our volcanic tremor model by including acoustic vibration in magma; and development of a high-temperature small-diameter borehole seismograph for use in search of a magma reservoir by listening to seismic events due to thermal stress. (ERA citation 07:061193)