skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Sequence stratigraphy of Plio-Pleistocene strata in the south additions: Offshore Louisiana

Conference · · AAPG Bulletin (American Association of Petroleum Geologists); (USA)
OSTI ID:5922553
; ; ;  [1]
  1. TGS Offshore Geophysical Co., Houston, TX (USA)

TGS Offshore Geophysical Company and GECO Geophysical Corp. have conducted a regional sequence stratigraphic study of the Plio-Pleistocene in offshore Louisiana south additions. Strata are deposited along an unstable progradational continental margin and systems tracts differ greatly from those described for stable progradational continental margins. Delineation of these units required iterative analysis of seismic, wireline, and biostratigraphic data. Condensed intervals were interpreted from 45 wells. Lowstand slope-fans exhibit concave-upward reflections associated with reflections that downlap away from them, chaotic reflections, and thin parallel units. Reflections in lowstand prograding-wedge systems tracts exhibit divergence toward downthrown sides of growth faults. Unlike stable passive margins, progradational patterns are not observed. Both transgressive and highstand systems tracts generally exhibit concordant reflections. Oblique progradational patterns, common in highstand strata along stable progradational margins, are rare. These systems tracts also exhibit characteristic patterns on SP and resistivity well-logs. Basin floor-fans commonly exhibit well-defined blocky sandstones and excellent reservoir potential. Good reservoir sands are also present in the lowstand prograding wedge system tract, characterized by sand-rich coarsening-upward sequences. Lithology in the lowstand slope-fan systems tract is highly variable. However, prolific reservoirs are present in channel facies, which exhibit blocky or fining-upward sequences. Reservoir quality is generally poor in the transgressive systems tract and highstand systems tract. This approach allows systems tracts to be correlated throughout the Gulf Coast Basin and effectively used to time geologic events in the basin and to predict location of reservoir and seal strata.

OSTI ID:
5922553
Report Number(s):
CONF-9010204-; CODEN: AABUD
Journal Information:
AAPG Bulletin (American Association of Petroleum Geologists); (USA), Vol. 74:9; Conference: Gulf Coast Association of Geological Societies and Gulf Coast Section of SEPM (Society of Economics, Paleontologists, and Mineralogist) meeting, Lafayette, LA (USA), 17-19 Oct 1990; ISSN 0149-1423
Country of Publication:
United States
Language:
English