Since Leonardo da Vinci made his first environmental analysis in the 15th century, geologists have become increasingly concerned with sedimentary environments. Accordingly, their methods for recognizing environments of deposition have become more sophisticated, and their determinations have become more precise.

The major types of criteria conventionally used in recognizing sedimentary environments are the physical, chemical, and biologic characteristics preserved in the rock. These features can be determined from a single small outcrop or subsurface core. Where larger or multiple outcrops are accessible, or where numerous subsurface cores are available, criteria of a much larger order of magnitude, such as lateral and vertical facies relations and the three-dimensional geometric framework of the strata, can be employed to strengthen and broaden the environmental interpretation.

In the symposium papers presented at this meeting, the speakers review the major sedimentary environments and identify for each the unique set of criteria which permit its recognition. Such information is important, not only to interpret the stratigraphic record, but also to explore for and produce most natural resources, including oil and gas, mineral deposits, and underground water supplies. Knowledge of sedimentary environments also is essential in engineering-geology studies of numerous and diverse types.

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