Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Sprenke, K. F. Articles by Stickney, M. C. Search for Related Content GeoRef GeoRef Citation

Comparison of Body-Wave Displacement with Damage Observations of a Rockburst, Coeur d'Alene Mining District, Idaho

Geological Sciences
University of Idaho
Moscow, Idaho 83844
(K.F.S.)
Spokane Research Laboratory
315 E. Montgomery
Spokane, Washington 99207-2291
(B.G.W., J.K.W.)
Battelle Memorial Institute
Pacific Northwest Division
Richland, Washington 99352
(A.C.R.)
Earthquake Studies Office
Montana Bureau of Mines and Geology
Butte, Montana 59701
(M.C.S.)

Manuscript received 1 February 2001.

Fault-plane solutions for seismic events in the deep underground mines of the Coeur d'Alene Mining District in northern Idaho have been difficult to reconcile with actual observations of mine damage. Examination of rockburst damage in stopes as well as measurements of slip movements on bedding planes suggests that rockbursts in the Lucky Friday Mine are closely associated with gradual bedding-plane slip. This progressive slip reduces the physical dimensions of stopes and increases compressive stress resulting in sudden implosive failure of the stope margins. Thus, much of the difficulty in evaluating seismological data arises from the implosional nature of these rockbursts, making the first motion of the events difficult to interpret. In the summer of 1998, we acquired several months of high-quality seismic data from five stations in the vicinity of the Lucky Friday Mine. This is the first time that a network of high dynamic-range, three-component instruments has been deployed in this mining district. On 29 August, 1988 at 6:09 UTC, a M_L 2.9 event occurred at the Lucky Friday Mine. This event resulted from bedding-plane slip and caused extensive damage in the mine that was carefully documented. Using a least-squares procedure, we were able to find a well-constrained moment tensor solution that matches the P and S displacement amplitudes measured at the five temporary stations. We derived a model of the mechanism to compare with the underground observations of bedding-plane slip and damage. We conclude that high-quality seismological instrumentation is required if meaningful results are to be obtained for understanding the source mechanisms of shear-implosional rockbursts.