Microseismic activity induced by hydraulic mining of steeply inclined coal seams
A microseismic monotoring facility was applied to observe rock failure associated with the hydraulic mining of steeply inclined coal seams, where seismometers were so arranged on the surface and underground that a seismic array could almost enclose the mining panels. The seismic foci distributed uniformly at one view over the mining panels, however, a considerable number of seismic events were concentrated within a few zones bounded on the pre-existing faults. The distribution of seismic foci in regard to the distance from the plane of the coal seam was approximated by the normal distribution whose mean value and standard deviation were 16 - 34 m from the seam plane and 43 - 51 m around the mean value respectively. An analysis revealed that the maximum compression axis at the seismic focus might be in good agreement with the dip direction of the coal seam, whilst the maximum tension axis was nearly allied to the normal direction of the coal seam. A comparison of microseismic activity between before and after mining of seams showed that the spatial rate of seismic energy in preceding mining was about more than 7.0 times higher than that of in successive mining.
- Research Organization:
- Hokkaido Univ., Sapporo, Japan
- OSTI ID:
- 6740498
- Report Number(s):
- CONF-811036-
- Journal Information:
- Ser. Rock Soil Mech.; (United States), Conference: 3. conference on acoustic emission/microseismic activity in geologic structures and materials, University Park, PA, USA, 5 Oct 1981
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
58 GEOSCIENCES
COAL MINES
SEISMICITY
COAL MINING
HYDRAULICS
ROCKS
FAILURES
MONITORING
SEISMIC SURVEYS
FLUID MECHANICS
GEOPHYSICAL SURVEYS
MECHANICS
MINES
MINING
SURVEYS
UNDERGROUND FACILITIES
012000* - Coal
Lignite
& Peat- Mining
580100 - Geology & Hydrology- (-1989)