A Survey of Mining Associated Rockbursts
Abstract
Parameters related to rockbursts, specifically types of ore, mining operation, magnitude-frequency statistics, maximum magnitudes, depths, and presence of precursory phenomena, are compiled for various tectonic/geologic regions. Data from Canada, the United States, Great Britain, Sweden, West Germany, Poland, Czechoslovakia, South Africa, the USSR, China, Japan, and Australia are tabulated and sorted according to type of geologic conditions. Similarities and differences in source characteristics between rockbursts and natural crustal earthquakes are examined and classified. Type I rockbursts are directly related to an advancing mine face; Type II events involve induced movement along preexisting fault planes. Reliability of prediction of the maximum size of rockbursts based upon mine area, excavation rate, geology, and extent of fracturing of adjacent rock is assessed with special focus on consistency between different areas of the world. The number of Type I rockbursts is found to be a direct function of excavation rate; their locations are consistently determined by location of the mine face and by local geological structure. When Type I events results in new fracture planes, high stress drops result. It is possible that an inactive fault can be activated by the presence of a mine, resulting in Type II rockbursts. Search for reliable precursory phenomena has been unsuccessful. The upper limit for Type I events seems to be controlled by the strength of the rock, whereas the upper limit for Type II events is a completely open question at this time. Induced seismicity; Rock mechanics.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 02, 1988
- Accession Number
- ADA206891
Entities
People
- Janet C. Johnston
Organizations
- Air Force Research Laboratory