Tectonic history of coal-bearing sediments in eastern Pennsylvania using coal reflectance anisotropy

Thesis/Dissertation · Sat Jan 01 00:00:00 EST 1983

OSTI ID:6205910

Levine, J R

Geologic stresses during coalification impart an anisotropic reflectance fabric to coal, which was investigated by analysis of oriented coal samples. The reflectances from three nearly perpendicular sections were employed in constructing a three-dimensional model of reflectance, represented diagramatically by the coal reflectance indicatrix (CRI). The three principal axes of the CRI (RMAS, RINT and RMIN) can be used as indicators of strain paths and timing of tectonic events. Nonoriented samples also were used to estimate the magnitudes of the principal axes, using a new mathematical procedure. Coal rank patterns, as indicated by the mean reflectance of outcropping coal beds, show higher ranks in the center of the Western Middle field than on the adjacent margins. This appears to be a consequence of the less competent coal-bearing rocks in the center of the basin being uplifted with respect to the margins along high-angle reverse faults late in the coalification history. Several lines of evidence indicate that the paleogeothermal gradient in the Anthracite basin was normal (ca. 33/sup 0/C/km). Hence, the west to east increase in coal rank resulted from increasing depths of burial. A body of high-density material in the Precambrian basement, indicated by the Scranton Gravity High, may have caused crustal downwarping which could partially account for the large sedimentary thicknesses in the region. Much of the thick overburden which formerly overlaid the coals may have been emplaced in the form of a nappe rather than by sedimentary processes.

• OSTI ID: 6205910
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL
REFLECTIVITY
COAL DEPOSITS
TECTONICS
AGE ESTIMATION
METAMORPHISM
PENNSYLVANIA
VARIATIONS
CARBONACEOUS MATERIALS
ENERGY SOURCES
FEDERAL REGION III
FOSSIL FUELS
FUELS
GEOLOGIC DEPOSITS
MATERIALS
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NORTH AMERICA
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RESOURCES
SURFACE PROPERTIES
USA
011000* - Coal
Lignite
& Peat- Reserves
Geology
& Exploration