Anatomy of a Pleistocene Sedimentary Sequence

Peter K. Trabant

Climatic fluctuations and correlative changes in sea level, attributed primarily to variations in solar insolation over the past 126,000 years, have produced a well defined stratigraphic sequence of the 4th order.

A number of studies from widespread geographical areas and sedimentary settings document the climatic and oceanographic records for this period, from which a sketchy record of the precise timing of cyclostratigraphic processes is emerging. While large-scale Milankovitch effects on climate and sea level are understood, the Late Pleistocene cyclostratigraphic record is beginning to reveal small scale details indicative of a punctuated equilibrium dominated system. A system in which steady state depositional environments are only very briefly affected by rapid sedimentary processes.

Understanding the precise timing of these short period effects and sedimentary processes provide answers on the formation of stratigraphic sequences and systems tracts, and how these can be applied to investigations of the geological record in the exploration for hydrocarbons.

AAPG Search and Discovery Article #91020©1995 AAPG Annual Convention, Houston, Texas, May 5-8, 1995