Karst development in the Tobosa basin (Ordovician-Devonian) strata in the El Paso border region of west Texas

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

OSTI ID:6138210

Lemone, D V ^[1]

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1. Univ. of Texas, El Paso, TX (United States). Dept. of Geological Sciences

Karst development within the Tobosa basin strata in the El Paso border region is best displayed during two time intervals: Middle Ordovician (27 Ma) developed on the Lower Ordovician El Paso Group and Middle Silurian to Middle Devonian (40 Ma) karst developed on the Lower-Middle Fusselman Formation. These major exposure intervals are recognized in regional outcrops as well as in the subsurface of the Permian Basin where they form major reservoirs. Minor local karsting is noted also within and upon the Upper Ordovician (Montoya Group) and within the shoaling upward members of overlying the Fusselman Formation. Middle Ordovician karsting with major cavern development extends down into McKellingon Canyon Formation approximately 1,000 feet below the top of the Lower Ordovician El Paso Group. The McKellingon is overlain by the cavern roof-forming early diagenetic dolomites, lower Scenic Drive Formation which in turn is overlain by the locally karsted upper Scenic Drive and Florida Mountains formations. Collapse of the overlying Montoya Group into El Paso Group rocks is observed. The Fusselman Formation rests disconformably on the Montoya Group. It is a massive, vuggy, fine- to coarsely-crystalline, whitish dolomite. Extensive karsting has developed on the top of the Fusselman. The middle Devonian Canutillo Formation with a basal flooding deposit overlies this karst surface. Minor karsting following fracture systems extends from the major karst of the El Paso Group up into the major karst in the Fusselman. The karst seems to be following and developing along the same linear fracture systems. If so, it is not unreasonable to interpret these fracture systems as being inherited from the earlier Precambrian structures underlying them.

• OSTI ID: 6138210
• Report Number(s): CONF-9303212-; CODEN: GAAPBC
• Journal Information: Geological Society of America, Abstracts with Programs; (United States), Vol. 25:1; Conference: 27. annual Geological Society of America (GSA) South-Central Section meeting, Fort Worth, TX (United States), 15-16 Mar 1993; ISSN 0016-7592
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
GEOLOGIC FORMATIONS
CAVES
GEOLOGIC FRACTURES
TEXAS
CARBONATE ROCKS
DEVONIAN PERIOD
DISSOLUTION
GEOLOGIC HISTORY
ORDOVICIAN PERIOD
SEDIMENTARY BASINS
CAVITIES
DEVELOPED COUNTRIES
GEOLOGIC AGES
GEOLOGIC STRUCTURES
NORTH AMERICA
PALEOZOIC ERA
ROCKS
SEDIMENTARY ROCKS
USA
580000* - Geosciences