Paleoenvironments and hydrocarbon potential of Upper Jurassic Norphlet Formation of southwestern Alabama and adjacent coastal water area

Conference · Sat Sep 01 00:00:00 EDT 1984 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:6297350

Mancini, E A; Mink, R M; Bearden, B L

Upper Jurassic Norphlet sediments in southwestern Alabama and the adjacent coastal water area accumulated under arid climatic conditions. The Appalachian Mountains of the eastern United States extended into southwestern Alabama, providing a barrier for air and water circulation during Norphlet deposition. Norphlet paleogeography was dominated by a broad desert plain rimmed to the north and east by the Appalachians and to the south by a developing shallow sea. Initiation of Norphlet sedimentation was a result of erosion of the southern Appalachians. Norphlet conglomerates were deposited in coalescing alluvial fans in proximity to an Appalachian source. The conglomeratic sandstones grade downdip into red-bed lithofacies that accumulated in distal portions of alluvial fan and wadi systems. Quartzose sandstones (Denkman Member) were deposited as dune and interdune sediments on a broad desert plain. The source of the sand was the updip and adjacent alluvial fan, plain, and wadi deposits. A marine transgression was initiated late in Denkman deposition, resulting in the reworking of previously deposited Norphlet sediments. Norphlet hydrocarbon potential in southwestern and offshore Alabama is excellent with four oil and gas fields already established. Petroleum traps discovered to date are primarily structural traps involving salt anticlines, faulted salt anticlines, and extensional fault traps associated with salt movement. Reservoir rocks consist of quartzose sandstones, which are principally eolian in origin. Smackover algal carbonate mudstones were probably the source for the Norphlet hydrocarbons.

• Research Organization: Alabama State Oil and Gas Board, Tuscaloosa
• OSTI ID: 6297350
• Report Number(s): CONF-8410143-
• Journal Information: Am. Assoc. Pet. Geol., Bull.; (United States), Vol. 68:9; Conference: 34. annual meeting of the Gulf Coast Association of Geological Societies and Gulf Coast Section of SEPM, Shreveport, LA, USA, 24 Oct 1984
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
ALABAMA
NATURAL GAS DEPOSITS
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCE POTENTIAL
SEDIMENTATION
COASTAL REGIONS
GEOLOGIC FORMATIONS
JURASSIC PERIOD
SOURCE ROCKS
FEDERAL REGION IV
GEOLOGIC AGES
GEOLOGIC DEPOSITS
MESOZOIC ERA
MINERAL RESOURCES
NORTH AMERICA
RESOURCES
USA
020200* - Petroleum- Reserves
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& Exploration
030200 - Natural Gas- Reserves
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& Exploration