Datapages, Inc.Print this page

Abstract: A Revised Cenozoic Geochronology: Template for Global Stratigraphic Correlations and Petroleum Exploration in the 1990s

William A. Berggren, Marie-Pierre Aubry

An internally consistent and geologically precise (if not accurate) time scale provides a high resolution framework for global stratigraphic correlation, a sine qua non of a meaningful historical geology. At the same time it provides a rigorous framework for local/regional correlations which forms the basis of petroleum exploration.

A revised Cenozoic global polarity time scale (GPTS) based on a reanalysis of sea floor spreading patterns and a (re)assessment of radioisotopic ages of the past decade serves as a template for magnetobiochronologic (re)calibrations of about 150 pre-Pliocene planktonic foraminiferal and 100 calcareous nannoplanktonic datum events and 45 Pliocene and 10 Pleistocene planktonic foraminiferal datum events.

This poster display emphasizes: (1) the revised magneto-biochronologic calibrations and duration of each of the Cenozoic epochs; (2) the revised age estimates and duration of chronostratigraphic units/boundaries; (3) revised age estimates of biostratigraphic zonal/boundary markers and biochronal durations; (4) integrated biostratigraphic/biochronologic and seismic stratigraphy case history studies of the Gulf Coast and Atlantic Coastal Plains Neogene. Numerous regional unconformities [with hiatuses ranging from <0.5 m.y. to (approx.) 5 m.y.] are seen to correspond to seismically identified sequence boundaries. Some of these unconformities appear to correlate with globally correlative glacio-eustatic sea level falls, whereas others do not, suggesting a significant local to regional ectonic component to the formation of some unconformities in the stratigraphic record. Tectonically induced slumping on the continental margins may have been a significant factor.

AAPG Search and Discovery Article #90951©1996 AAPG International Conference and Exhibition, Caracas, Venezuela