Hydrogeologic factors affecting cavern morphology within rocks of Mississippian age in northwestern Arkansas

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

OSTI ID:5888292

Fanning, B J ^[1]; Brahana, J V ^[2]

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1. Univ. of Arkansas, Fayetteville, AR (United States). Dept. of Geology
2. Univ. of Arkansas , Fayetteville, AR (United States). Geological Survey

Cavern development within rocks of Mississippian age in northwestern Arkansas is associated with two Pleistocene erosional features, the Boston Mountains Plateau and the Springfield Plateau. Each plateau is characterized by a distinct stratigraphic sequence with unique lithologies. Cavern morphology (both cross-sectional and planimetric) in each plateau is the result of the complex interaction of numerous hydrogeologic factors. Four of the most dominant factors which affect cavern morphology appear to be: (1) composition and continuity of the confining units; (2) percentage of noncarbonate components in rocks of the cavern-forming interval; (3) nature and distribution of ground-water recharge to the cavern-forming interval; and (4) nature and distribution of fractures within the cavern-forming interval. Network maze patterns typically develop in the Pitkin Limestone, the formation in which most caverns form beneath the Boston Mountains Plateau. The Pitkin, a bioclastic limestone, is confined above by siltstones of the Cane Hill member of the Hale Formation and below by shales of the Fayetteville Formation. The maze pattern indicates that these caverns probably were formed by dissolution of the rock matrix by diffuse recharge moving vertically through leaky confining units. Single rooms are the dominant cavern morphology in the chert-dominated Boone Formation of the Springfield Plateau. Where the concentration of chert is greater than 50 percent, the Boone lacks structural integrity and fails to develop well-integrated conduit networks. Point recharge features in outcrop areas of the Boone Formation are not visible in most of the Springfield Plateau because the insoluble residuum masks the upper bedrock surface. Where the Boone Formation is less than 7 meters thick, surface karst features are more prevalent.

• OSTI ID: 5888292
• Report Number(s): CONF-9303212--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:1
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ARKANSAS
CARBONATE ROCKS
CARBONIFEROUS PERIOD
CAVES
CAVITIES
DEVELOPED COUNTRIES
DISSOLUTION
DISTRIBUTION
GEOLOGIC AGES
GEOLOGIC FORMATIONS
GEOLOGY
GEOMORPHOLOGY
GROUND WATER
HYDROGEN COMPOUNDS
HYDROLOGY
LIMESTONE
NORTH AMERICA
OXYGEN COMPOUNDS
PALEOZOIC ERA
REGIONAL ANALYSIS
ROCKS
SEDIMENTARY ROCKS
SITE CHARACTERIZATION
SPATIAL DISTRIBUTION
STRATIGRAPHY
USA
WATER