Lacustrine sedimentation and origin of the Upper Pennsylvanian Redstone limestone, northern Appalachian basin

Conference · Mon Mar 01 04:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5722418

Eggleston, J R ^[1]

---

1. Geological Survey, Reston, VA (United States)

The Redstone limestone occurs in a 7- to 12-m interval between the underlying Pittsburgh and overlying Redstone coal beds. The thickness of the Redstone limestone, which is up to 12 m, varies laterally. The Redstone is sometimes partially or totally replaced by a fluvial siliciclastic unit, which formed either penecontemporaneous or just prior to the limestone. Two cores and an outcrop of Redstone limestone in northern West Virginia were studied in detail. X-ray mineralogical analyses indicate that the limestone is predominantly calcite, ankerite, and quartz, with minor amounts of dolomite, chert, pyrite, feldspar, and clay minerals. Six carbonate facies were identified. The predominant facies is a pedogenic breccia facies that contains typical paleosol features, such as peds and root traces, and represents periods of subaerial exposure of the sediment. A fossiliferous facies contains an abundance of ostracod and mollusk fossilized shells; nested ostracod shells and the occurrence of a shallow-water gastropod, Anthracopupa sp., suggest a shallow-water origin. A bioturbated facies exhibits disrupted bedding and burrows filled with detrital material. The micritic facies contains predominantly calcite and ankerite grains less than 30 microns in diameter and exhibits no apparent bedding. A laminated facies is characterized by two distinct types of lamination: one type is created by interbedding of quartz, clay minerals, plant material, and calcite and/or ankerite and could be caused by periodic storms; the other type contains interbeds of rhombohedral ankerite within predominantly micritic calcite, which could be caused by changes in climate or lake conditions. In summary, petrographic and sedimentological analyses indicate that the Redstone limestone probably formed in a shallow, widespread lake or series of lakes.

• OSTI ID: 5722418
• Report Number(s): CONF-9303211--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:2
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CARBONATE ROCKS
CARBONIFEROUS PERIOD
COHERENT SCATTERING
DEPOSITION
DEVELOPED COUNTRIES
DIFFRACTION
DRILL CORES
GEOLOGIC AGES
GEOLOGIC FORMATIONS
GEOLOGY
LIMESTONE
MINERALOGY
NORTH AMERICA
PALEOZOIC ERA
PETROGRAPHY
ROCKS
SCATTERING
SEDIMENTARY ROCKS
STRATIFICATION
STRATIGRAPHY
USA
WEST VIRGINIA
X-RAY DIFFRACTION