Sequence stratigraphic and depositional framework of the paleocene lower Wilcox Strata, northwest Gulf of Mexico basin

Conference · Wed Sep 01 04:00:00 EDT 1993 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:6964850

Xue, L; Galloway, W E ^[1]

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1. Univ. of Texas, Austin, TX (United States)

The lower Wilcox (LW) strata comprise a single genetic sequence and are subdivided into four subsequences (I-IV, from oldest to youngest) based on regional flooding surfaces. The LW sequence is bounded by maximum flooding surfaces associated with the Big Shale at the top and Midway marine shale at the bottom, and is dated at 56.5 Ma and 59.0 Ma. The LW sequence shows extensive shelf-margin progradation, high sedimentation rate, and thick progradational parasequences. LW depositional systems are outlined on the basis of the net-sandstone isopach maps, which are contoured using a log database of about 500 wells. Subsequence I includes several fluvial-dominated delta systems, reflecting the initial progradation of the LW depositional episode. Subsequence III contains the classic Rockdale delta system, Cotulla barrier-bar system, and strand plain system described by Fisher and McGowen. Subsequence III is the turning point of the depositional styles within the LW genetic sequence. The progradational patterns of sequences I and II were replaced by the retrogradational style of subsequence III, which contain s deposits of wave-dominated delta, strand plain, barrier-bar, lagoon, and shelf-slope systems. Subsequence IV also shows a wave-dominated style. Several wave-dominated delta systems migrated landward. The delta-type evolution in the Houston embayment (major depocenter) from fluvial-dominated through wave-modified, to wave-dominated and backstepping delta systems reflects the progression from progradational subsequences I and II to retrogradational subsequences III and IV.

• OSTI ID: 6964850
• Report Number(s): CONF-9310237--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (United States) Journal Volume: 77:9
• 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
ATLANTIC OCEAN
CARIBBEAN SEA
CENOZOIC ERA
DEPOSITION
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC STRATA
GEOLOGIC STRUCTURES
GEOLOGY
GULF OF MEXICO
ROCKS
SEAS
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEDIMENTATION
SHALES
STRATIGRAPHY
SURFACE WATERS
TERTIARY PERIOD
WELL LOGGING