The Annona Chalk is a geologic formation in Arkansas, Texas, Louisiana, and Oklahoma.

The formation is a hard, thick-bedded to massive, slightly fossiliferous chalk.

Fossils in the Annona Chalk include coelenterates, echinoderms, annelids, bivalves, gastropods, cephalopods, and some vertebrate traces.

[3] The beds range in thickness, up to over 100 feet in depth in some areas (such as at White Cliffs).,[4] but thins to the east and is only a few feet thick north of Columbus, Arkansas and is completely missing to the east.

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