Regional geological framework and petroleum geology of Miocene sandstones in coastal and offshore Alabama

Conference · Fri May 01 04:00:00 EDT 1987 · AAPG (Am. Assoc. Pet. Geol.) Bull.; (United States)

OSTI ID:6219447

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

The Miocene natural gas trend of coastal and offshore Alabama is part of the regional Miocene oil and gas trend of the Gulf coastal area that extends from Texas into Alabama. The major Miocene productive area in Alabama is in southern Baldwin County and Mobile Bay. Since the discovery of Miocene gas in 1979, 28 natural gas fields have been established in coastal and offshore Alabama. The Miocene sandstones range in thickness from 10 to 200 ft, are very fine to coarse grained, are quartz rich, and have subangular to rounded and moderately to well-sorted quartz grains. The productive Miocene interval overlies upper Oligocene marine shelf deposits (Chickasawhay Limestone) and is overlain by Miocene fluvial clastics. The Miocene sandstones, which include the Amos, Escambia, Luce, and Meyer, are interpreted to represent a marine shelf-deltaic complex. A Miocene delta system prograded from the west in the area of offshore Louisiana-Mississippi into coastal and offshore Alabama. Reservoirs and potential reservoirs include highly constructive and highly destructive deltaic and marine shelf sandstones. Porosity in these sandstones is primary intergranular and generally ranges from 27 to 35%. Permeabilities may exceed 2000 md. Basinal Miocene marine clays and Oligocene marls are the probable petroleum source rocks. Petroleum traps are principally stratigraphic, typically involving lateral sandstone pinch-outs against regional dip. Seismic reflection is an excellent exploration tool for identifying potential Miocene fields. Miocene gas sands are best delineated with relative-amplitude seismic reflection data on which gas-charged sands are apparent as bright spots.

• Research Organization: Univ. of Alabama, Tuscaloosa
• OSTI ID: 6219447
• Report Number(s): CONF-870606-
• Conference Information: Journal Name: AAPG (Am. Assoc. Pet. Geol.) Bull.; (United States) Journal Volume: 71:5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
ALABAMA
CENOZOIC ERA
EXPLORATION
FEDERAL REGION IV
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC TRAPS
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NORTH AMERICA
OFFSHORE SITES
PERMEABILITY
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY ROCKS
TERTIARY PERIOD
USA