Regional diagenetic variation in Norphlet sandstone: Implications for reservoir quality and the origin of porosity

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

OSTI ID:6130155

Kugler, R L; McHugh, A ^[1]

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1. Univ. of New Orleans, LA (USA)

Although deeply buried (18,000->20,000 ft) eolian and reworked marine Norphlet arkose and subarkose in Mississippi, Alabama, and Florida have been intensely studied by several workers, fundamental questions remain regarding diagenetic controls on reservoir quality and the origin of porosity. In spite of a regionally uniform framework composition of quartz, albite, and potassium feldspar, the diagenetic character of the unit is variable on a scale ranging from individual laminations to single hydrocarbon-producing fields to areas encompassing several fields or offshore blocks. The presence or absence of clay minerals in various forms clearly is a dominant control on porosity-permeability trends. In deep reservoirs in Mobile Bay and offshore Alabama and Florida, petrographic evidence for dissolution of pervasive authigenic carbonate and/or evaporite minerals to produce high secondary porosity values is equivocal or absent. Although evidence exists for some secondary porosity, much porosity appears to be relict primary porosity. On a regional scale, including both onshore and offshore areas, sandstones with radial, authigenic chlorite coats consistently have high porosity and permeability. In Mobile Bay and offshore Alabama, the distribution of this form of chlorite may be controlled by the presence of precursor clay/iron-oxide grain coats. The occurrence of these coats likely is related to environment of deposition.

• OSTI ID: 6130155
• 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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& Exploration
58 GEOSCIENCES
580000 -- Geosciences
ALABAMA
CHALCOGENIDES
CLAYS
DEPOSITION
DIAGENESIS
DISTRIBUTION
ELEMENTS
EXPLORATION
FEDERAL REGION IV
FELDSPARS
FLORIDA
GEOLOGIC DEPOSITS
GEOLOGIC FAULTS
GEOLOGIC FORMATIONS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
IRON
METALS
MINERAL RESOURCES
MINERALS
MISSISSIPPI
NORTH AMERICA
ORIGIN
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PERMEABILITY
PETROLEUM DEPOSITS
POROSITY
PRODUCTION
QUARTZ
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SILICON COMPOUNDS
SILICON OXIDES
TRANSITION ELEMENTS
USA