Investigations of differential strata movements and water table fluctuations during longwall operations at the Somerset Mine No. 60. Final technical report as of 15 October 1978

Technical Report · Wed Nov 01 04:00:00 EST 1978

DOI:https://doi.org/10.2172/5983001· OSTI ID:5983001

Barla, G. B.; Boshkov, S.

This research work was directed toward the acquisition of data describing the phenomenology of failure of superincumbent strata during longwall mining operations in the Pittsburgh coal seam. The specific site for the study was the second panel in the Somerset Mine No. 60, belonging to the Bethlehem Steel Company, and located near Washington, Pennsylvania. The thickness of the coal approximated 68 inches. Two boreholes were instrumented as strata movement monitoring stations, drilled from the surface to the coal seam, which was located under 330 feet to 430 feet of cover. Five additional holes were drilled to an approximate depth of 150 feet in order to permit observations on the water table fluctuations. Cores recovered from the two instrumented boreholes were geomechanically logged throughout. The recorded data indicate that strata behavior differs in locations close to the first break from those which follow the establishment of regular caving. The fracture of impermeable layers inevitably leads to sudden drops in the water table. The data suggest the existence of a very steep angle of fracture growth coupled to an immediate propagation upward for the caved area.

• Research Organization: Columbia Univ., New York (USA)
• OSTI ID: 5983001
• Report Number(s): FE-9041-1
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
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47 OTHER INSTRUMENTATION
COAL MINING
DATA
DATA FORMS
EXPERIMENTAL DATA
EXTENSOMETERS
GEOLOGY
GROUND SUBSIDENCE
GROUND WATER
HYDROGEN COMPOUNDS
INFORMATION
LEVEL INDICATORS
LONGWALL MINING
MEASURING INSTRUMENTS
MINING
MONITORING
NUMERICAL DATA
OXYGEN COMPOUNDS
STRATA MOVEMENT
TABLES
UNDERGROUND MINING
WATER