The White Rim Sandstone Member of the Permian Cutler Formation in Canyonlands National Park, Utah, was deposited in a coastal eolian environment. This conclusion is based on sedimentary structures, petrologic features, and stratigraphic relations. The White Rim consists of two major genetic units. These units may represent a coastal dune field and related interdune ponds. Distinctive sedimentary structures of the coastal dune unit include large to medium-scale, unidirectional, tabular planar cross-bedding; high-index ripples paralleling dip direction of the foresets; raindrop impressions; slump marks; and coarse-grained lag layers. Also, a predominant northwest to southeast orientation of the cross-bedding agrees with the paleowind direction proposed in this area for Perm an time. Distinctive sedimentary structures of the interdune pond unit include wavy, horizontally laminated bedding, adhesion ripples, and desiccation(?) polygons. These features may have been produced by water-table fluctuations.

Petrologic characteristics of the White Rim help to define the depositional environment as coastal. A crinoid fragment was identified at one location; heavy minerals are present in both units; and small amounts of well rounded, reworked glauconite are present throughout the study area.

The White Rim Sandstone Member was deposited during a period of changing sea level and migrating strandlines. Continental sedimentation was dominant in eastern Utah, along the ancestral Uncompahgre Mountains; and marine deposition was prevalent in western Utah. Rocks deposited in the two environments interfinger in the Canyonlands area. Previous authors have proposed that the White Rim represents either a shallow-marine or eolian facies equivalent to both the upper part of the Toroweap Formation and the Gamma Member of the Kaibab Limestone. Results from this study suggest that the White Rim more likely represents eolian deposition on a prograding shoreline characterized by a semiarid climate and predominantly onshore winds.

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