Sedimentary structures in shoreface deposits are in marked contrast with those of laterally equivalent facies. Whereas sediments of the beach and offshore areas consist of clean sands inhabited by relatively few species of burrowing organisms, the shoreface is characterized by an abundant and diverse fauna inhabiting detritus-rich, muddy sand. Principal sedimentary structures of shoreface deposits are those produced by biogenic reworking, whereas in the laterally equivalent beach and offshore sediments, structures which reflect physical energy are more abundantly represented. Examples of ancient nearshore sediments indicate that these characteristic features of the shoreface are valid facies indicators in the sedimentary record.

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