180 likes | 204 Views
History of Arizona’s Colorado Plateau and Related Landforms. GCU 221. Game Plan:. Cenozoic history of the Colorado Plateau - Time step 1 – Compression (Kaibab Plateau) - Time step 2 – Extensive Ponding and Deposition - Time step 3 – Local Ponding / Deposition ( Bidahochi )
E N D
History of Arizona’s Colorado Plateau and Related Landforms GCU 221
Game Plan: • Cenozoic history of the Colorado Plateau - Time step 1 – Compression (Kaibab Plateau) - Time step 2 – Extensive Ponding and Deposition - Time step 3 – Local Ponding / Deposition (Bidahochi) - Time step 4 – Erosion (Grand Canyon) - Time step 5 – Extension (Hurricane Cliffs)
Cenozoic History of the Colorado Plateau • Time Step 1 - 60 to 40 million years ago Compression formed a bunch of broad domal uplifts, sags, and laccoliths across the Colorado Plateau
Cenozoic History of the Colorado Plateau • Time Step 1 - 60 to 40 million years ago Kaibab Plateau (Domal Uplift)
Cenozoic History of the Colorado Plateau • Time Step 1 - 60 to 40 million years ago St. John’s Sag (Synclinal downwarp)
Cenozoic History of the Colorado Plateau • Time Step 1 - 60 to 40 million years ago Igneous Intrusion – Kind of similar to a Metamorphic Core Complex, but more related to compression instead of extension Navajo Mountain (laccolith)
Cenozoic History of the Colorado Plateau • Time Step 2 - 40 to 20 million years ago Bryce Canyon and the Claron Formation Drainage northeasterly onto the Colorado Plateau from the Mogollon Highlands, leads to wide spread lake and river deposition.
Cenozoic History of the Colorado Plateau • Time Step 2 - 40 to 20 million years ago Bryce Canyon and the Claron Formation
Cenozoic History of the Colorado Plateau • Time Step 2 - 40 to 20 million years ago Green River Formation and the Flagstaff Limestone
Cenozoic History of the Colorado Plateau • Time Step 3 – 20 to ~5 million years ago Extension breaks apart the Mogollon Highlands and disrupts drainage leading to deposition on the southern edge of the Colorado Plateau.
Cenozoic History of the Colorado Plateau • Time Step 3 – 20 to ~5 million years ago Bidahochi Formation – Where was the Colorado River at this time?
Cenozoic History of the Colorado Plateau • Time Step 4 – ~5 to ~1 Grand Canyon incision leads to dramatic drop in base level.
Cenozoic History of the Colorado Plateau • Time Step 4 – ~5 to ~1 How did the Colorado River cross the Kaibab Upwarp?
Cenozoic History of the Colorado Plateau • Time Step 4 – ~5 to ~1 Can you say KNICKPOINTS!?!
Cenozoic History of the Colorado Plateau • Time Step 5 – ~1 to the present Extension is moving onto the Colorado Plateau Hurricane Fault
Cenozoic History of the Colorado Plateau • Time Step 5 – ~1 to the present Extension is moving onto the Colorado Plateau Hurricane Fault
Things to know: • Colorado Plateau History - Time step 1 – Compression (Kaibab Plateau) - Time step 2 – Extensive Ponding and Deposition northwest drainage (Rim Gravels) - Time step 3 – Local Ponding / Deposition (Bidahochi) - Time step 4 – Erosion (Grand Canyon) southwest drainage (Colorado River) - Time step 5 – Extension (Hurricane Cliffs) Questions: Ask Dr. Douglass