ABSTRACT: Interpreting Sequence Stratigraphic Architecture from Biostratigraphic Signatures: Case Studies from the Northern Gulf of Mexico

JONES, GARRY D.

Digital capture of microfossil data from well and outcrop samples permits rapid computer analysis and plotting of biostratigraphic range charts, cross plots, and "curves". Integrating these biostratigraphic plots with log and seismic data indicates the microfossil record reliably characterizes the key stratal surfaces (flooding surfaces and sequence boundaries) which underpin the interpretation of sequence stratigraphic architecture.

Using in-house software (The Integrated Paleontologic System=IPS), I generated and interpreted biostratigraphic plots integrated with log data for >200 wells in the northern Gulf of Mexico. The well sections range in age from Oligocene to Pleistocene and represent deposition in fluvio-deltaic through lower-bathyal paleoenvironments. Field- to exploration-scale case studies illustrate the value of using biostratigraphic signatures to help solve geologic problems via an integrated, sequence-stratigraphic approach.

IPS-generated paleobathymetry curves covering various chronostratigraphic intervals from many Gulf locations provide the raw material for defining local to regional, relative sea-level events. Also, the vertical succession of paleobathymetry changes associated with higher-order sequences can produce unique stratigraphic signatures useful for detailed correlation.

Future research should (1) document biostratigraphic signatures across well-constrained cycles in sea level from different dip positions and accomodation settings; (2) apply numerical techniques to integrate biostratigraphic data with log and seismic attributes and achieve computer-generated geologic interpretations.

AAPG Search and Discovery Article #90941©1997 GCAGS 47th Annual Meeting, New Orleans, Louisiana