Kaibab Limestone and Associated Strata, Circle Cliffs , Utah

Abstract

Exposed Permian rocks studied in the Circle Oiffs region are the upper part of the White Rim Sandstone Formation of the Cutler Group and the overlying Kaibab Limestone. The former is composed of calcareous and dolomitic sandstones and sandy dolomites formed under stable tectonic conditions in a nearshore marine environment by reworking of the underlying aeolian portion of the White Rim Member. The Kaibab Limestone is actually a slightly calcareous, partly sandy, glauconitic dolomite which was chiefly a biomicrite before dolomitization. It formed in shallow, though quiet, marine waters under tectonically quiescent conditions. It disconformably overlies the White Rim Sandstone. Detrital intertidal and very shallow subtidal sediments of the lowermost Moenkopi Formation (Triassic), mostly chert breccias, overlie the irregular, partly channeled surface of the Kaibab Limestone. This ' attests to post-Kaibab emergence and erosion. Uniformity of lithologies and thicknesses of individual Permian beds traced across the Circle Cliffs Anticline demonstrate the absence of a late Permian paleostructure.