Isotope Chronostratigraphy: High-Resolution Stratigraphic Correlations in Deep-Water Exploration Tracts of Northern Gulf of Mexico: ABSTRACT

Abstract

ABSTRACT On-going stable isotope research with cuttings from over 16 Plio-Pleistocene deep-water wells has established a high-resolution framework for chronostratigraphic tie-lines between Plio-Pleistocene wells. Detailed oxygen isotope (O-18/O-16) records from core material and sixteen exploration wells at 30 intervals provide a large data base by which to establish a chemical stratigraphy record for the Gulf of Mexico. This type section is used to evaluate the stratigraphic integrity of exploration wells and the timing and reliability of important calcareous nannofossil and foraminiferal biostratigraphic datums. Within this framework, freshwater discharge events and local/regional unconformities can be defined with high precision. The record can be used to relate large-scale and fine-scale changes in 1) sediment accumulation rates, 2) the distribution of sand-shale facies, and 3) seismic sequence boundaries of glacio-eustatic cycles. Integration of this information can lead to a more precise definition of the timing and extent of target sand bodies in deep-water exploration tracts.