FILLON, RICHARD H., Texaco, Inc., New Orleans, LA

ABSTRACT: System Tract History Analysis: Key to Understanding Deposition in Cored Reservoir Analog Units on the Shelf

An analytical procedure, shelf system tract history analysis, has been developed to integrate high-resolution biochronostratigraphy, sediment accumulation, compaction-induced subsidence, and late Quaternary sea level records into a detailed accommodation-space framework for characterizing system-tract deposition. The technique, a modification of geohistory analysis, has been profitably applied to section cored on the mid-Louisiana shelf in approximately 70 m of water. Analysis of the cored section places a wave-based-induced erosional fourth-order sequence boundary at approximately 75 Ka, within the isotope stage 4 sea level lowstand. Analysis further indicates that a channel-cut, forced regression surface, within a reservoir analog lowstand delta unit marks a more-than 30-m terrace e tant during a part of the intense isotope stage 2 sea level lowstand which culminated at approximately 18 Ka. Bounding transgressive and highstand system tracts are consistent with deposition in middle neritic depths (approximately 60-90 m).

AAPG Search and Discovery Article #90989©1993 GCAGS and Gulf Coast SEPM 43rd Annual Meeting, Shreveport, Louisiana, October 20-22, 1993.