<P> The oldest beds of this formation belong to the Dinosaur Canyon Member, a reddish, slope - forming rock layer with thin beds of siltstone that are interbedded with mudstone and fine sandstone . The Dinosaur Canyon, with a local thickness of 140 to 375 feet (43 to 114 m), was probably laid down in slow - moving streams, ponds and large lakes . Evidence for this is in cross-bedding of the sediments and large numbers of fish fossils . </P> <P> The upper member of the Moenave is the pale reddish - brown with a thickness of 75 to 150 feet (23 to 46 m) and cliff - forming Springdale Sandstone . It was deposited in swifter, larger, and more voluminous streams than the older Dinosaur Canyon Member . Fossils of large sturgeon - like freshwater fish have been found in the beds of the Springdale Sandstone . The next member in the Moenave Formation is the thin - bedded Whitmore Point, which is made of mudstone and shale . The lower red cliffs visible from the Zion Human History Museum (until 2000 the Zion Canyon Visitor Center) are accessible examples of this formation . </P> <P> At 200 to 600 feet (61 to 183 m) thick, the Kayenta Formation's sand and silt were laid down in early Jurassic time in slower - moving, intermittent streambeds in a semiarid to tropical environment . Interbedded sandstone, basal conglomerates, siltstones, mudstones, and thin cross-beds are typical channel and floodplain deposits found in the Kayenta . Paleocurrent studies show that the Kayenta rivers flowed in a general westward to southwestward direction . </P> <P> Fossilized dinosaur footprints from sauropods have been found in this formation near the Left Fork of North Creek . Mountains in Nevada and California continued to rise in the Lower Jurassic as plate motions forced North America northward . Eventually, this created a rain shadow and brought widespread desertification . Today the Kayenta is a red and mauve rocky slope - former that can be seen throughout Zion Canyon . </P>

What kind of rock is zion national park