Summary

The Wingate Sandstone provides a record of the earliest development of basinwide eolian environments in the Mesozoic over the central Colorado Plateau. The formation represents a transition from the previous fluvial-dominant depositional systems of the Triassic into the widespread eolian environments of the Early Jurassic. The Wingate contains seven major eolian erg sequences separated by regional bounding surfaces or correlative strata, distinguishable across the central Colorado Plateau. The deposits enclosed in erg sequences were produced by predominantly oblique or compound dunes influenced by cyclic fluctuations in wind regimes. Strata representing deposition primarily during periods of erg hiatus were produced in sabkha, sand sheet, and aqueous environments.

The reconstruction of sedimentation history indicates that erg deposition occurred in cycles across the basin, punctuated by periods of deflation over an equivalent geographic extent. These periods of erg development and hiatus were related to fluctuations in sediment supply, possibly facilitated by recycling of alluvial material from Moenave fluvial systems into the Wingate. Persistent geographic variations in sedimentation within the basin can be discerned through successive periods of erg development from the close of Chinle deposition to the initiation of Kayenta fluvial systems.