ABSTRACT: Seismic Facies of Mesozoic-Cenozoic Strata in the Perdido Fold Belt
FIDUK, JOSEPH C., PAUL WEIMER, BRUCE D. TRUDGILL, MARK G. ROWAN, PETER E. GALE, BRYANT E. KORN, RONALD L. PHAIR, GENEVA R. ROBERTS, WILLIAM T. GAFFORD, CINDY K. GUU, and ROGER LOWE
The Perdido Fold belt, within US waters of the northwestern deep Gulf of Mexico, is a late Paleogene to early Neogene structural province comprising several large anticlinal closures. Seismic analysis defines the sequence stratigraphy of the Jurassic through Recent section and along with structural restorations, delineates pre-growth (Jurassic-Eocene), syn-growth (Oligocene-early Miocene), and post-growth (middle Miocene-Recent) intervals. All stratigraphic interpretations are based on seismic data only.
The Jurassic through Lower Cretaceous interval is capped by the prominent middle Cretaceous sequence boundary. This interval is characterized by high amplitude, low frequency, laterally continuous reflections of uniform thickness that are interpreted as a series of primarily deep-water carbonates. The Upper Cretaceous interval has similar seismic character but of lower amplitude, possibly suggesting dilution of carbonate deposition by pelagic/hemipelagic sedimentation. The Paleocene interval is characterized by moderate to low amplitude, discontinuous reflections that thicken to the west. Subtle erosional features and slightly mounded reflections suggest stacked turbidite systems, and reflect the onset of siliciclastic deposition. The thick Eocene interval is characterized by an upward increase in frequency content and seismic reflection strength, interpreted to reflect interbedded hemi-pelagic sediments with turbidite systems. Oligocene to middle Miocene sediments deposited between folds display tilted onlapping or flat onlapping relationships with the folds. These reflections are interpreted to represent clastic growth and infill strata respectively. Overlying the fold belt, well imaged late Miocene to Recent sediments were deposited with chaotic, trough, and mounded reflection geometries. These are interpreted as an interbedded series of slides and submarine fan deposits.
AAPG Search and Discovery Article #90941©1997 GCAGS 47th Annual Meeting, New Orleans, Louisiana