Quantitative Chemical Stratigraphy of Offshore Exploration Wells, Northern Gulf of Mexico

Dwight M. Trainor, Douglas F. Williams, Ian Lerche

Isotope chronostratigraphy is now a proven form of chemical stratigraphy for high-resolution stratigraphic correlations in late Miocene through Pleistocene sections of exploration wells from the northern Gulf of Mexico (GOM). Detailed oxygen and carbon isotope records from wells spanning the GOM margin from Mississippi Canyon to East Breaks permit the development of a GOM "type" chemical stratigraphic section. The use of modern techniques of signal-to-noise identification enable us to compare our regional GOM type section to the global isotope record derived from deep-sea sections using coherence, auto-correlation, cross-correlation, and spectral analysis. These quantitative techniques enable us to recognize nearly 200 oxygen and carbon isotope zones or stages in the Plio ene-Pleistocene. This chemical stratigraphy zonation offers unparalleled, fine-scaled correlation and depositional modeling of exploration wells. Removal of the global isotope signal from the regional GOM record permits us to determine the effects of meltwater-fluvial discharge episodes and regional sea level fluctuations on sedimentation along the GOM margin.

AAPG Search and Discovery Article #91030©1988 AAPG Annual Convention, Houston, Texas, 20-23 March 1988.