The White Rim Sandstone is a

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

located in southeastern

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

. It is the last member of the

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

Cutler Group The Cutler Formation or Cutler Group is a rock unit that is exposed across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian epoch. Descri ...

, and overlies the major

Organ Rock Formation The Organ Rock Formation or Organ Rock Shale is a formation within the late Pennsylvanian to early Permian Cutler Group and is deposited across southeastern Utah, northwestern New Mexico, and northeastern Arizona. This formation notably outcrops ar ...

and

Cedar Mesa Sandstone Cedar Mesa Sandstone (also known as the Cedar Mesa Formation) is a sandstone memberThe Cutler Formation is sometimes classified as the Cutler Group, in which case Cedar Mesa Sandstone is classified as a formation rather than a member. of the Cutle ...

; and again overlies thinner units of the Elephant Canyon and Halgaito Formations. The ''White Rim'' is eponymous, as the sandstone is named for its prominent white color, and forms the rims of cliffs.

Geology

It is the continental

deposited at the time of

marine transgression A marine transgression is a geologic event during which sea level rises relative to the land and the shoreline moves toward higher ground, which results in flooding. Transgressions can be caused by the land sinking or by the ocean basins filling ...

s during the Early to Middle

Period. ;Toroweap Formation The

coeval {{Short pages monitor Sandstone formations of the United States Geologic formations of Utah Colorado Plateau Permian geology of Utah Cisuralian Series of North America Cutler Formation