ostracodes. The Owl Rock erodes into littered slopes and is found directly below the Wingate Sandstone along the Waterpocket Fold's west face. Glen Canyon Group (Triassic) All three formations of the Glen Canyon Group were laid down in the Mid to Late Triassic during a time of increasing aridity. Slightly clockwise and northward movement of the North American Plate was bringing the area into a dryer climatic belt. The direction of cross-bedding in Glen Canyon Group sand dunes suggests that prevailing winds from the north transported the sand into the region. Outcrops of the Glen Canyon Group's three formations are the most prominently exposed rock layers in the spine of the Waterpocket Fold. Together they reach a thickness of 1,500 to 2,700 feet (460 to 820 m) in the area and their sandstones are seen in many of the arches, domes and slot canyons in Capitol Reef. They are, from oldest (lowest) to youngest (highest); Wingate Sandstone Kayenta Formation Navajo Sandstone Sand dunes migrated back and forth on the shore of the Sundance Sea, creating the 350 foot (107 m) thick cliff-forming Wingate Sandstone. This formation is composed of orange-colored cross bedded fossilized sand dunes made of fine-grained and well-rounded quartz sand. Wingate outcrops are found capping the Waterpocket Fold's western escarpment. Prominent examples are easy to see near the Visitor Center in the Fruita Cliffs and in The Castle. The climate became more humid later in Triassic time. Slow-moving, southwestward flowing braided streams laid down thin-bedded layers of sand, silt, mud and cobbles in channels, across low flood plains and in lakes. Fossilized footprints of dinosaurs and the crocodile-like tritylodonts can be found in this 350 foot (107 m) thick ledgy-slope forming formation, called the Kayenta. The Kayenta weathers into three units; a lower ledge and middle cliff that are dominated by cross-bedded sandstone and an upper slope that has relatively more siltstone. It is often difficult to spot the contact between the Windgate and Kayenta due to their similar color and grain size. One place where the contact is easiest to discern is west of State Route 24 along the Fremont River at mile marker 82. A massive Sahara-like desert geologists call an erg then invaded the area, covering it with 800 to 1,100 feet (240 to 335 m) of accumulated white to tan-colored fossilized sand dunes. The resulting formation, called the Navajo Sandstone, is composed of cross-bedded