Classification of peat as a basis for modeling coal quality

Conference · Tue Jan 01 04:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6336282

Neuzil, S G; Cecil, C B

A major portion of the quality characteristics of a coal bed is related to the peat stage of coal formation. Peat formation may result from either topogenous or ombrogenous conditions. Topogenous peat is confined to topographic depressions and is characterized by a relatively horizontal upper surface having a random mosaic distribution of flora. Water influx may add suspended sediments and dissolved solids that influence peat chemistry by partially buffering organic acids and causing a mildly acidic environment (pH 4+ to approx.7). Significant levels of microbial activity can develop. Ombrogeneous peat occurs only where precipitation is sufficient to maintain a raised water table within the peat. The peat deposits are characterized by a domed morphology having a zoned floral distribution and outward surface drainage. Precipitation contributes a low concentration of dissolved solids that are insufficient to buffer organic acids of the peat, thus causing a highly acidic environment (pH approx. 3-4). Microbial degradation is minimal under these conditions. The resulting ombrogenous peat in general has 1) a slightly degraded fibric texture, 2) a high C/N ratio, and 3) low and more uniform ash and sulfur content. Interpreting the peat stage depositional environment of a coal bed as either topogenous or ombrogenous should be useful in predicting coal quality. Mineral matter and maceral content and composition of coal should indicate 1) sapric to hemic texture and high and variable ash content of topogenous peat or 2) fibric texture and low and uniform ash content of ombrogenous peat.

• Research Organization: Geological Survey, Reston, VA (USA)
• OSTI ID: 6336282
• Report Number(s): CONF-8510489-
• Conference Information: Journal Name: Geol. Soc. Am., Abstr. Programs; (United States) Journal Volume: 17
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010600* -- Coal
Lignite
& Peat-- Properties & Composition
011000 -- Coal
Lignite
& Peat-- Reserves
Geology
& Exploration
CARBONACEOUS MATERIALS
CHEMICAL COMPOSITION
COAL
COAL DEPOSITS
COAL RANK
COALIFICATION
DEPOSITION
DIAGENESIS
ENERGY SOURCES
FOSSIL FUELS
FUELS
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGIC MODELS
GEOLOGY
GROUND WATER
HYDROGEN COMPOUNDS
MACERALS
MATERIALS
MINERAL RESOURCES
ORGANIC MATTER
ORIGIN
OXYGEN COMPOUNDS
PEAT
PETROGRAPHY
PETROLOGY
RESOURCES
WATER
WATER INFLUX