Abstract: Interrelationship of Marginal-Marine Depositional Environment Classifications

FRITSCHE, A. EUGENE

Studies on present-day marginal-marine depositional environments tend to be restricted to single depositional systems when the goal of such studies is to determine the characteristics that will allow differentiation between wave-, river-, and tide-dominated settings. Such studies are easily restricted to single depositional settings because the geographic limits are clearly visible. As a result of these studies, classification schemes have been proposed that divide the wave-, river-, and tide-dominated depositional systems into discernible sedimentary environments and subenvironments. Although changes in facies along a coastline from one depositional system to another are understood, the relationship of environments in one classification system to those in another has not been sufficiently emphasized. Stratigraphic-analysis research on ancient rock units is hindered if the researcher tries to make an interpretation that is based on the environmental classification scheme of a single depositional system, when in reality the rocks being analyzed were originally deposited as sediment in the boundary region between two or more depositional systems. The author presents an environmental classification scheme relating tidal range to dominant process involved. Recognizing and making interpretative use of this classification scheme among the environments in the three major marginal-marine depositional systems will improve and help to fine-tune the results of future stratigraphic-analysis research.

Search and Discovery Article #90945©1997 AAPG Pacific Section Meeting, Bakersfield, California