Biogenic sedimentary structures offer a new and exciting approach to the interpretation of ancient sedimentary environments. Although trace fossils have been studied extensively by European geologists since early in this century, it is only in recent years that they have received much more than passing mention in North America. The increased interest in tracks, trails, burrows, and borings is due primarily to the environmental or facies approach to the study of sedimentary rocks. Whereas, in the past, attention has been directed toward descriptive studies of rock units, the present paleoecologic approach demands a genetic interpretation of the sedimentary record.

Appreciation of biogenic sedimentary structures as facies indicators has been influenced significantly by the emphasis on studies of physical sedimentary structures which in the past two decades have introduced many new keys to paleoenvironment interpretation. Additional impetus to the utilization of trace fossils has come from detailed studies of modern sediments which illustrate clearly the important relations that exist between the animals and sediments in a particular environment.

In the study of ancient and present-day nearshore sedimentary environments, the facies significance of biogenic sedimentary structures can be demonstrated readily. Striking similarities exist between nearshore clastic facies of Holocene and Pleistocene sediments of the Georgia coast and Upper Cretaceous shorelines of the western interior. Such similarities dramatically point out the value of trace fossils in environmental interpretation. These comparisons exist not only on the regional stratigraphic level but also between and within specific facies. Field studies which utilize trace fossils in conjunction with physical sedimentary structures, lateral and vertical changes in the sedimentary sequence, and geometry of the rock body offer new opportunities in the search for stratigraphic ccumulations of oil and gas.

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