Clay veins: Their occurrence, characteristics, and support

Book · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6965472

Chase, F E; Ulery, J P

These detrimental aspects have prompted the Bureau of Mines to investigate the physical characteristics of and roof instability problems associated with clay veins. The investigators found that clay veins normally occur in more stable, less rapidly subsiding coal basins. Clay veins result when tensile stresses develop fissures that are later infilled. These fissures can be propagated by compactional processes and/or tectonic stresses during and subsequent to coalification. The Bureau also found that associated faults, fractures, and slickenside planes commonly parallel clay veins and disrupt the lateral continuity of the immediate and, sometimes, main roof. When clay veins parallel or subparallel the direction of face advance, the roof is segmented into cantilever beams, causing unstable conditions. Consequently, the strate on either side of the clay veins should be bolted and strapped together to form a beam.

• OSTI ID: 6965472
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
012010* -- Coal
Lignite
& Peat-- Mining-- Planning & Surveying-- (1987-)
58 GEOSCIENCES
580300 -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
CLAYS
COAL DEPOSITS
COAL SEAMS
COALIFICATION
CRACK PROPAGATION
GEOLOGIC DEPOSITS
GEOLOGIC FISSURES
GEOLOGIC STRUCTURES
MECHANICS
MINERAL RESOURCES
NATIONAL ORGANIZATIONS
PHYSICAL PROPERTIES
RESOURCES
ROCK MECHANICS
ROOFS
TECTONICS
US BUREAU OF MINES
US DOI
US ORGANIZATIONS