The Middle Jurassic Carmel Formation of southern Utah is divided into two informal members deposited during a major transgressive-regressive cycle. The relatively thin lower member was deposited in a shallow, subtidal, marine to coastal, sabkha environment that advanced southeastward, onlapping and reworking coastal dunes of the Navajo and Page sandstones. Lithofacies of the lower Carmel include calcareous mudstone, bivalve micrite, oolitic grainstone and packstone, ostracod pelletal micrite, dolomicrite, algal stromatolites, aphanitic dolomite, and minor nodular gypsum and sandstone.

The sporadic northwest retreat of the Carmel Sea and progradation of coastal sabkha and continental sabkha and dune sediments is recorded in the thick upper member of the Carmel. Lithofacies include algal stromatolites, aphanitic dolomite, calcareous mudstone, nodular gypsum, horizontal to gnarly-bedded sandstone, and cross-bedded sandstone.

The lower Carmel undergoes rapid west to east thinning and facies changes, indicating that during the early Middle Jurassic (late Bajocian) the Hurricane fault was a tectonic hinge line that separated a westward tilting unstable shelf slope to the west from an unstable shelf to the east. Furthermore, lower Carmel facies, isopach anomalies, and regional stratigraphic and structural correlations indicate that anomalous subsidence and sedimentation in the present Sevier-Paunsagunt fault zone were contemporaneous and genetically related to initial deformation of the Middle Jurassic San Pete-Sevier rift of the hinge-line region of central Utah.

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