A subsurface study of the Denkman sandstone member, Norphlet Formation, hatters Pond field, Mobile County, Alabama

Conference · Sat Sep 01 04:00:00 EDT 1990 · AAPG Bulletin (American Association of Petroleum Geologists); (USA)

OSTI ID:5991309

Young, L M; Anderson, E G; Baria, L R ^[1]; Higginbotham, R S

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1. Northeast Louisiana Univ., Monroe (USA)

Hatters Pond field is in east-central Mobile County in southwestern Alabama and it produces from both the Norphlet and Smackover formations. The structural trap involves salt movement along the west side of the Mobile Fault System that resulted in a faulted salt anticline. The Norphlet Formation of southwestern Alabama consists of red to gray siltstone and pinkish to gray sandstone with conglomerate layers. Three facies have been distinguished within the Norphlet Formation: a lower shale, a red siltstone sequence, and an upper quartzose unit. The thickness of the formation ranges from a feather edge to more than 800 ft (234.8 m) in southwestern Alabama. The Upper Jurassic Denkman Sandstone Member of the Norphlet Formation at Hatters Pond field is a medium- to fine-grained, well-sorted arkosic sandstone between the underlying Norphlet redbed lithofacies and the carbonates of the overlying Smackover Formation. Here, the Denkman Member can be subdivided into a massive upper unit and a low- to high-angle cross-stratified lower unit. The sandstones are quartz-rich with a high percentage of feldspars. The majority of the feldspar grains observed are potassium feldspar. Microcline is usually less altered when compared with other types of feldspar grains. The major types of feldspar replacement include illitization, hematitization, dolomitization, chloritization, calcitization, vacuolization, and anhydritization. Carbonate replacement of feldspars is very abundant, mostly by ferroan dolomite. Rock fragments are not abundant in the Denkman Member, although there is good evidence of a metamorphic/volcanic source area. The sandstones are cemented by dolomite, calcite, anhydrite, and quartz and feldspar overgrowths. The lower Denkman unit is slightly more porous than the upper Denkman unit. The pore-lining authigenic clay, illite, greatly reduces permeability and porosity in these sandstones.

• OSTI ID: 5991309
• Report Number(s): CONF-9010204--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Journal Volume: 74:9
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
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58 GEOSCIENCES
580000 -- Geosciences
ALABAMA
CHALCOGENIDES
CLAYS
DEPOSITION
DIAGENESIS
FEDERAL REGION IV
FELDSPARS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC FORMATIONS
GEOLOGIC TRAPS
JURASSIC PERIOD
MESOZOIC ERA
MINERAL RESOURCES
MINERALS
NORTH AMERICA
OIL FIELDS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PERMEABILITY
PETROLEUM DEPOSITS
POROSITY
QUARTZ
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY ROCKS
SILICON COMPOUNDS
SILICON OXIDES
SILTSTONES
USA