Geology of the West-Central Part of the Gunnison Plateau, Utah

Marine Jurassic pelecypods from central and southern Utah

“…The overall characteristics and distribution of the Carmel Formation have been described by Baker, Dane, and Reeside (1936, p. 6, 45, 54, 58) and have been summarized recently by Wright and Dickey (1958, p. 174, 175;1963). The characteristics and distribution of the Arapien Shale have been described by Spieker (1946, p. 123-125), Hardy (1952a), Hardy and Zeller (1953, p. 1264-1266, and Willard and Callaghan (1962).…”

Structure and stratigraphy of Upper Cretaceous and Paleogene strata (North Horn Formation), eastern San Pitch Mountains, Utah — Sedimentation at the front of the Sevier orogenic belt

“…This convention marks a major break with previous nomenclature (for example, Spieker, 1949a, b;Hardy and Teller, 1953;Weiss 1982;Weiss and Roche, 1988). Our reasons for this change are several: (1) the lithology of conglomerates previously designated Price River in the San Pitch Mountains is dissimilar to the sandstone and siltstone of type exposures of the Price River Formation (Spieker and Reeside, 1925) in the northeastern Wasatch Plateau; (2) the outcrops of the San Pitch Mountains are not continuous with those in the type area to allow direct tracing of units; and (3) conglomerate units designated as Price River by Hardy and Zeller (1953) in the southwestem part of the San Pitch Mountains are not demonstrably continuous with basal conglomerate units of the North Horn along the eastern range front (Lawton and Trexler, 1991). The inconsistency of Price River usage in the San Pitch Mountains was also recognized by Mattox (1987), who did not apply the Price River nomenclature in the southwestern part of the range.…”

“…The maximum thickness of the formation is not known exactly because a thrust fault omits part of the section at Big Mountain (plate 1), the location of the thickest stratigraphic section; however, the North Horn is known to pinch out completely both east and west of the study area. In the subsurface to the east, the North Horn thins onto a thrusted structure beneath Sanpete Valley (Stahdlee, 1982;Lawton, 1985); westward, it thins above tilted older Cretaceous strata overlain by the Flagstaff Limestone on the west side of the range (Hardy and Zeller, 1953;Lawton, 1985).…”

Stratigraphic and time-stratigraphic cross sections: A north-south transect from near the Uinta Mountain axis across the Basin and Range transition zone to the western margin of the San Rafael Swell, Utah

“…In addition, beds exposed in the upper 177 ft of the Twist Gulch Formation near Salina Canyon (Willis, 1986) are similar to beds of the Curtis Formation exposed on the San Rafael Swell, which Imlay (1980) considered to be upper middle Callovian. However, Villien and Kligfield (1986) found Early Cretaceous palynomorphs in rocks mapped as Twist Gulch Formation by Hunt ( 1950) and Hardy and Zeller (1953) along Chicken Creek in the Gunnison Plateau. Au by (1991) assigned rocks that were previously included in the upper part of the Twist Gulch Formation by Hunt (1950) and Hardy and Zeller (1953) to the Lower Cretaceous Cedar Mountain Formation.…”

“…However, Villien and Kligfield (1986) found Early Cretaceous palynomorphs in rocks mapped as Twist Gulch Formation by Hunt ( 1950) and Hardy and Zeller (1953) along Chicken Creek in the Gunnison Plateau. Au by (1991) assigned rocks that were previously included in the upper part of the Twist Gulch Formation by Hunt (1950) and Hardy and Zeller (1953) to the Lower Cretaceous Cedar Mountain Formation. The rocks described by Villien and Kligfield (1986) probably belong to the Cedar Mountain Formation, not the Twist Gulch Formation.…”