Depositional Modeling of Detrital Rocks: With Emphasis on Cored Sequences of Petroleum Reservoirs

Studies of cores from both field and wildcat wells offer the opportunity to interpret subsurface rock sequences and relate them to surface sections, to calibrate mechanical logs with observed lithologies, and to use these data to enhance both field development drilling and wildcat exploration. The cored sequences of detrital rocks described in this core workshop are organized on the basis of depositional models, and presented sequentially down the depositional system through the continental environments to the shoreline zone, and, finally, to the shallow offshore and deeper water environments. Each of the depositional models is treated in separate sections in which diagrams, facies descriptions and terminology are presented that summarize the principal aspects of the model.
Deltaic and Interdeltaic Coastal Plain and Shoreline Environments Available to Purchase
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Published:January 01, 1985
Abstract
Within the coastal plain and shoreline zone, two principal coastal environments are distinguished--deltaic, and interdeltaic (or nondeltaic between major deltas, Fig. 5.1). Deltaic areas develop where relatively large river systems empty at the shoreline zone and deposit volumes of sediment that accumulate at rates generally greater than the rate at which modifying shoreline processes can disperse them (Fig. 5.2), or subsidence or sea level rise can overcome them. In contrast, nondeltaic areas receive much less sediment from river systems; wave and tidal action become more dominant, and barrier islands grow by accretion of sediments from the seaward and longshore directions. In both areas, lateral accretion greatly exceeds vertical accumulation, and vertical profiles reflect progradation of higher-energy facies over lower-energy facies (Fig. 5.3).