Exposure: The Kayenta is exposed throughout the state of Utah, but is especially visible in Zion National Park, Capital Reef and Glen Canyon NRA. Age: Early Jurassic, 199.6 million years ago to 175.6 million years ago. Depositional Environment: Fluvial (river) environment The Navajo Sandstone was deposited in an eolian environment composed of large sand dunes, similar […]
Exposure: The Navajo is exposed throughout the state of Utah, but reaches maximum thickness near Zion National Park and Red Rocks Recreation area near Las Vegas. Age: Early JurassicThe Navajo Sandstone is dated as Early Jurassic, although precise dating is typically difficult due to a lack of age diagnostic fossils, a common problem in eolian […]
Exposure: The Temple Cap is exposed exclusively in the Southwest corner of Utah (atop the spires of Zion National Park), whereas the Page Sandstone stretches all the way into the center of the state. Both share similiar ages, but the Page is thicker and was formed by a separate erg, with far less marine influence. […]
Exposure: Within the Grand Staircase, the Curtis Formation is best exposed in east of Capital Reef National Park just south of Goblin Valley State Park. Age: Middle Jurassic, 160 Ma Depositional Environment: Full marine, shallow marine to sabkha (and supratidal) Paleogeography: Frequent, but short-lived sea level fluctuations during the Middle to Late Jurassic caused periodically flooding […]
Exposure: Without a doubt the most striking exposures of the Entrada Formation are in Arches National Park. Other great exposures exist in Canyonlands, Goblin Valley State Park and Lake Powell NRA. Age: Upper Jurassic, 80 and 140 ma Depositional Environment: Eolian, sabkha, and tidal flat. The Entrada Sandstone preserves terrestrial environments. Within the field trip area, the deposits […]
Exposure: Within the Grand Staircase, the Curtis Formation is best exposed in east of Capital Reef National Park just south of Goblin Valley State Park. Age: Deposited from early to late Oxfordian time (161 – 155 Ma) (Wilcox, 2007). Depositional Environment: Marine and marginal-marine tidal flat. Comprises one unconformably-bound, transgressive-regressive (T-R) sequence (Wilcox, 2007). Paleogeography: A major […]
Exposure: Within the Grand Staircase, the Summerville Formation is best exposed in east of Capital Reef National Park just south of Goblin Valley State Park. Age: Deposited Middle Jurassic, early to late Oxfordian time (161 – 155 Ma) (Wilcox, 2007). Depositional Environment: Marginal marine and sabkha/tidal. One unconformably-bound, transgressive-regressive (T-R) sequence, marine (saline lacustrine?) and marginal-marine (Wilcox, […]
Exposure: Within the Grand Staircase, the Morrison Formation is best exposed in Capital Reef National Park. Age: Late Jurassic (Kimmeridgian) 155-148 Ma Depositional Environment: Alluvial plain, fluvial channels and floodplains with paleosols Tectonics: Subduction to the west created a back arc rift basin (between Morrison basin and paleo Pacific Ocean).Mountain ranges (rift shoulder) to the […]
. The Grand Canyon, a mile-deep chasm carved through millennia of Earth’s history, is not merely a spectacle of layered rock; it is a profound archive of ancient life. Within its vibrant strata, beyond the skeletal remains, lie the subtle yet powerful narratives of behavior etched in stone: tracksites and trace fossils. These ichnological treasures, […]
What are Moqui Marbles? Moqui marbles are small, brownish-black balls composed of iron oxide and sandstone that formed underground when iron minerals precipitated from flowing groundwater. They occur in many places in southern Utah either embedded in or gathered loosely into “puddles” on the ground near outcrops of Jurassic age Navajo Sandstone.
