Entries by Lance Weaver

Curtis Formation (Geology of Utah’s Grand Staircase)

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 […]

Summerville Formation (Geology of Utah’s Grand Staircase)

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, […]

Morrison Formation (Geology of Utah’s Grand Staircase)

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 […]

When Was The Colorado River Formed?

Raise of the Colorado Plateau (33-15 MYA), and Formation of the Colorado River & Grand Canyon Introduction For over two decades, the geologic community has remained locked in a debate regarding the “Old” versus “Young” Colorado River, often missing the forest for the trees. By hyper-focusing on localized datasets—such as the geochemical signatures of the […]

Tracks, Traces & Other Fossils of The Grand Canyon & Grand Staircase

. 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, […]