Small to large-scale diagenetic variation in Norphlet sandstone, onshore and offshore Mississippi, Alabama, and Florida

Conference · Wed Mar 01 04:00:00 EST 1989 · AAPG Bull.; (United States)

OSTI ID:5796780

Kugler, R L

The detrital composition of Norphlet sandstone is relatively uniform on a regional scale, consisting of quartz, potassium feldspar, albite, and rock fragments comprised of these minerals. However, the diagenetic character of the sandstones is variable on a scale ranging from the individual laminations to single hydrocarbon-producing fields to regions encompassing several fields or offshore blocks. Small-scale variation results primarily from textural differences related to depositional processes in eolian and shallow marine systems. Degree of feldspar alteration and types of authigenic clay and carbonate minerals vary on a regional scale. Illite, dolomite, ferroan dolomite, and ferroan magnesite (breunnerite) are common in onshore wells in Alabama, whereas magnesium-rich chlorite and calcite are present in offshore Alabama and Florida. However, diagenetic character is more variable on a fieldwide scale than previously recognized. In Hatter's Pond field, Mobile County, Alabama, breunnerite, which has not been described previously in these sandstones, is the dominant cement in some wells but is absent others. Although illite is the most common authigenic clay throughout the field, chlorite is the most abundant clay in some wells. Because of uniformity of detrital composition, diagenetic variations cannot be related to differences in provenance, particularly on the scale of a single field. Factors that must account for variations in diagenesis include (1) differences in burial history relative to thermal sulfate reduction; (2) variation in fluid flow relative to subbasins, structural highs, fault systems, depositional texture, and early diagenetic character of the sandstones; and (3) variation in composition of underlying Louann evaporites.

• Research Organization: Univ. of New Orleans, LA (USA)
• OSTI ID: 5796780
• Report Number(s): CONF-890404-
• Conference Information: Journal Name: AAPG Bull.; (United States) Journal Volume: 73:3
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
ALABAMA
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CLAYS
DOLOMITE
FEDERAL REGION IV
FLORIDA
GEOLOGIC DEPOSITS
GEOLOGIC FAULTS
GEOLOGIC FORMATIONS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MATURATION
MINERAL RESOURCES
MINERALS
MISSISSIPPI
NORTH AMERICA
OXYGEN COMPOUNDS
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY ROCKS
USA