ABSTRACT

An historic overview of the development of chronostratigraphy of the continental slope of the northern Gulf of Mexico involves the history of concurrent developments in geoscience and technology. From the beginning of this century until after World War II, there was no chronostratigraphy as such. Biostratigraphy and lithostratigraphy provided a subsurface stratigraphic framework for the Gulf Coast in which "time lines" crossed "facies lines" in the cyclic series of regressions and transgressions of the Cenozoic. Zonation was based on benthic foraminifera in the transgressive shales. The electric log was the principal correlation tool after its introduction in the 1930's.

Following World War II, concepts progressed "from simplicity to complexity." Growth faults and depocenters were recognized. Research in ecology and paleoecology was applied to Gulf Coast problems and to the increased understanding of the relationship between biofacies and lithofacies. Planktonic zonation began to tie Gulf Coast stratigraphy to that of other regions. Advances in reflection seismology techniques stimulated offshore exploration.

From the 1960s on, the "plate tectonic revolution" and the Deep Sea Drilling Program influenced progress in development of magnetostratigraphy, radiometric dating, paleoclimatology and isotope stratigraphy, planktonic biostratigraphy, and related disciplines, all of which evolved into a useful chronostratigraphy. Continental slope exploration has resulted in significant discoveries in the "flexure trend."