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Heterostegina zone - A shallow Anahuac (Late Oligocene-Early Miocene) oil frontier in southern Louisiana and Mississippi

Conference · · AAPG Bulletin (American Association of Petroleum Geologists); (USA)
OSTI ID:5968009
 [1];  [2]
  1. Louisiana State Univ., Baton Rouge (USA)
  2. EuroBasin Petroleum Ltd., New Orleans, LA (USA)

The Heterostegina zone ({approximately}23.6-23.0 ma, N4a-Globorotalia kugleri zone) is recognized throughout the Gulf Coast as an excellent correlative datum and erratic but prolific producer of hydrocarbons. Its late Oligocene-early Miocene chronozone represents the maximum development of Neogene reefs in the Caribbean/West Atlantic biogeographic province. Although many of the western Gulf Coast Heterostegina reservoirs consist of reefal limestones that grew atop piercement salt domes, eastern Heterostegina equivalents in Louisiana (St. Martin Parish), southern Mississippi, and Alabama (Mobile Bay area) comprise a rimmed accretionary carbonate shelf. The existence of this shelf is confirmed by seismic data as well as by a core from the Sapphire Petroleum Company {number sign}1 State well (MS-85-4-OS) located south of Ship Island, Mississippi. Petrographic study of 17 ft of Anahua-cage core (5,660-5,677 ft) recovered from the Sapphire well has delineated three carbonate paleoenvironments-in ascending order: ( 1) shallow-water, windward algal thickets (5,671.0-5,677.0 ft); (2) bryozoan-mollusc-foraminiferal-algal limestones deposited below fairweather wave base (5,664.2-5,671.0 ft); and (3) foraminiferal-algal-rhodolitic limestone laid down above fairweather wave base (5,660.0-5664.2 ft).

OSTI ID:
5968009
Report Number(s):
CONF-9010204--
Journal Information:
AAPG Bulletin (American Association of Petroleum Geologists); (USA), Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Vol. 74:9; ISSN AABUD; ISSN 0149-1423
Country of Publication:
United States
Language:
English