Ronald J. Echols¹, John M. Armentrout¹, Steven A. Root¹, Larry B. Fearn¹, B. Kirby Rodgers¹, James C. Cooke¹, Peter R. Thompson²
(1) Mobil Technology Company, Dallas, TX
(2) Consultant

Abstract: Sequence stratigraphy of the Upper Eocene and earliest Oligocene: The record from southeastern Mississippi, USA

The eastern Gulf Coast Plain of the United States provides a richly fossiliferous sedimentary record for studying the sequence stratigraphy the Upper Eocene-Lower Oligocene. Strata of Clariborne, Jackson and Vicksburg stages show strong facies trends from east to west across Alabama and Mississippi. The study area in eastern Mississippi provides and intermediate position for integrating the stratigraphic records of the relatively thinner carbonate dominated systems of eastern Alabama and the thicker siliciclastic dominated systems of western Mississippi.

The sequence stratigraphic analysis is based on integration of data from three cores through the Upper Eocene and earliest Oligocene, five ‘classic’ outcrop localities, and distillation of the literature. Data from the cores and outcrops includes quantitative biostratigraphy of foraminifers, calcareous nannoplankton and palynomophs, palynofacies, wire-line logs, sedimentology of core and outcrop, magnetostratigraphy of core, preliminary strontium isotope ages, and basic organic geochemistry.

The sequence stratigraphic record is richly detailed with multiple condensed intervals suggesting over-printing of higher order sequences on 3rd -order sequences. The base of the Vicksburg may be a composite condensed section, consisting of a lower sediment starvation condensed section at the top of the Shubuta clay member, and an upper bypass condensed section within the Red Bluff Formation. A basal Vicksburg sequence boundary between these condensed sections, proposed by several previous workers, is possible but not definitive based on local evidence. A previously unrecognized condensed section within the regressive Forest Hill Formation is documented.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana