Sedimentology and stratigraphy of Mississippian orogenic sediments, east-central Nevada: proposed solution to a paradox

Conference · Fri Feb 01 04:00:00 EST 1985 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:5867058

Mason, R M

Mississippian orogenic sediments deposited during the Antler orogeny and exposed in east-central Nevada record the initial breakup of the Cordilleran geosyncline. They also contain one of the thickest, richest, yet most under-explored source rock-reservoir packages in the western US. Numerous geologists have studied the Chainman Shale-Diamond Peak Formation, yet the depositional setting of these formations, a factor critical to effective exploration for these attractive targets, is still controversial. In 1974, F.G. Poole suggested that the entire sequence was deposited as turbidites at abyssal depths, calling these rocks Antler flysch. B.R. Wilson and S.W. Laule thought these same sediments were largely nearshore marine to fluvial molasse sediments. Regional studies in east-central Nevada reveal 2 dramatically different facies within the Mississippian: a turbidite facies consisting of incomplete bouma sequences, interturbidite shales, and disordered conglomerates; and a fluvial-deltaic facies consisting of well cross-bedded, nearshore marine sandstones and fluvial conglomerates, nonmarine to shallow-marine shales, and marine limestones. In several areas these 2 facies are separated by only a few miles, yet structural juxtaposition is not likely. Rather, it appears the turbidite facies is older than the shallow-water facies and represents Early Mississippian in-fill of the narrow Antler trough. The fluvial-deltaic facies represents regressive deposition that prograded over the Antler trough in Late Mississippian time. Both facies contain rich source rocks and the more widespread fluvial-deltaic facies contains numerous reservoirs and potential stratigraphic traps.

• Research Organization: Southland Royalty Co., Denver, CO
• OSTI ID: 5867058
• Report Number(s): CONF-850322-
• Conference Information: Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Journal Volume: 69:2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
EXPLORATION
FEDERAL REGION IX
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC FORMATIONS
GEOLOGIC TRAPS
GEOLOGY
MINERAL RESOURCES
MISSISSIPPIAN PERIOD
NEVADA
NORTH AMERICA
PALEOZOIC ERA
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
SOURCE ROCKS
STRATIGRAPHY
USA