Coal mine bumps as related to geologic features in the northern part of the Sunnyside district, Carbon County, Utah

Journal Article · Fri Dec 31 04:00:00 EST 1993 · United States Geological Survey, Professional Paper

OSTI ID:482358

Osterwald, F W; Dunrud, C R; Collins, D S

Coal mine bumps, which are violent, spontaneous, and often catastrophic disruptions of coal and rock, were common in the Sunnyside coal mining district, Utah, before the introduction of protective-engineering methods, modern room-and-pillar retreat mining with continuous mining machines, and particularly modern longwall mining. The coal at Sunnyside, when stressed during mining, fails continuously with many popping, snapping, and banging noises. Although most of the bumps are beneficial because they make mining easier, many of the large ones are dangerous and in the past caused injuries and fatalities, particularly with room-and-pillar mining methods used in the early mining operations. Geologic mapping of underground mine openings revealed many types of deformational features, some pre-mine and some post-mine in age. Stresses resulting from mining are concentrated near the mine openings; if openings are driven at large angles to small pre-mine deformational features, particularly shatter zones in coal, abnormal stress buildups may occur and violent bumps may result. Other geologic features, such as ripple marks, oriented sand grains, intertongued rock contacts, trace fossils, and load casts, also influence the occurrence of bumps by impeding slip of coal and rocks along bedding planes. The stress field in the coal also varies markedly because of the rough ridge and canyon topography. These features may allow excessively large stress components to accumulate. At many places, the stresses that contribute to deformation and failures of mine openings are oriented horizontally. The stratigraphy of the rocks immediately above and below the mined coal bed strongly influences the deformation of the mine openings in response to stress accumulations. Triaxial compressive testing of coal from the Sunnyside No. 1 and No. 3 Mines indicates that the strength of the coal increases several times as the confining (lateral) stress is increased. 68 refs., 64 figs., 7 tabs.

• OSTI ID: 482358
• Journal Information: United States Geological Survey, Professional Paper, Journal Name: United States Geological Survey, Professional Paper Journal Issue: 1514; ISSN XGPPA9
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
36 MATERIALS SCIENCE
COAL
COAL DEPOSITS
COAL MINES
COMPRESSION STRENGTH
FAILURES
HAZARDS
MECHANICAL PROPERTIES
MINING ENGINEERING
SEDIMENTARY BASINS
UTAH