docThe Geology and Archeology of the Grand Canyon
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The Geology and Archeology of the Grand Canyon
The Geology and Archeology of the Grand Canyon Baron “Expedition”, Spring, 2007 Rock units of the Grand Canyon Abbott and Cook (2004) Precambrian Crystalline Rocks Abbott and Cook (2004) Precambrian Sediments Abbott and Cook (2004) Abbott and Cook (2004) Late Cenozoic Volcanics and Flood Deposits Abbott and Cook (2004) Fig. 18-7c, p. 424 Fig. 18-7c, p. 424 Fig. 18-7c, p. 424 Vishnu Schist Downstream of Bright Angel Trail Vishnu Schist Vishnu Schist Hugh and Mikey enter Horn Rapids Downstream of Bright Angel Trail Vishnu Schist Zoraster Granite Downstream of Bright Angel Trail Zoraster Granite intruding Vishnu Schist Precambrian Sediments Abbott and Cook (2004) Breakup of Rodinia www.nvcc.edu/home/cbentley/shenandoah/index.htm Breakup of Rodinia www.nvcc.edu/home/cbentley/shenandoah/index.htm Geology at a Divergent Plate Margin followed by a Passive Margin Geology at a Divergent Plate Margin followed by a Passive Margin Modern Passive Margin: North Carolina Modern Passive Margin: North Carolina Modern Passive Margin: North Carolina Geology at a Divergent Plate Margin followed by a Passive Margin Passive Margin: California ~700-300 Ma Passive Margin: Grand Canyon area ~700-300 Ma Latest Precambrian Paleogeography of Colorado Plateau Blakey and Ranney (2008) Precambrian Sediments Abbott and Cook (2004) Bass Limestone on Thunder Creek Trail tone s e m i L s Bas Thunder Creek t n Vish his c S u Stromatolites in Bass Limestone Schopf (2001) Hakatai Shale just above Hance Rapids Late Precambrian rift sediments and mafic ingeous rocks in North America Link et al. (1993) Late Precambrian rift sediments and mafic ingeous rocks in North America Link et al. (1993) Late Precambrian rift sediments and mafic ingeous rocks in North America Link et al. (1993) Crystal Springs and Becks Springs Formations, Saratoga Hills, CA rkopp rkopp Precambrian Sediments Abbott and Cook (2004) View NNE Upstream from Unkar Delta, Grand Canyon Dox Sandstone View NNE Upstream from Unkar Delta, Grand Canyon Dox Sandstone Cardenas Basalt Dox Sandstone Ripple marks in Precambrian Dox Sandstone near Unkar Delta, Grand Canyon reduced layer in Dox Sandstone Desert View Watchtower horizontal Paleozoic units Sa dipping Dox ndstone Abbott and Cook (2004) Tapeats Sandstone over Vishnu Schist Downstream from Bright Angel Trail Tapeats Sandstone over Vishnu Schist Downstream from Bright Angel Trail Great Unconformity (1200 million missing years) Tapeats Sandstone Vishnu Schist Great Unconformity in Blacktail Canyon Ken on air banjo.... “Deliverance” style Dave “Diego” Shapiro Tapeats Sandstone Vishnu Schist Muav Limestone Bright Angel Shale View upriver from Nankoweap Camp Bright Angel Shale Trilobite Trace Fossils, Grand Canyon, Az Bright Angel Shale Whitmore Wash, Grand Canyon Bright Angel Shale, Little Nankoweap Canyon, Grand Canyon Tapeats Sandstone, Deer Creek Trail, Grand Canyon Cruziana – trace fossil of furrowing trilobite Bright Angel Shale Formation near Whitmore Wash, Grand Canyon Wood Canyon Formation in Salt Spring Hills, CA Diplichnities – trace fossil of Isotelus trilobite walking upright Bright Angel Shale Fm. near Whitmore Wash, Grand Canyon Diplichnities – trace fossil of Isotelus trilobite walking upright Bright Angel Shale Fm. near Whitmore Wash, Grand Canyon Red Wall Limestone Matkatamiba Canyon Abbott and Cook (2004) Redwall Limestone Muav Limestone Redwall Limestone Muav Limestone Redwall Limestone “True Colors” Redwall Cavern Redwall Cavern Fossils-Crinoid stems Redwall Cavern Fossils-Crinoid stems Redwall Cavern Fossils-Brachiopods Redwall Limestone Fossils-Nautiloid Canyon Redwall Limestone Fossils-Nautiloid Canyon Redwall Limestone Fossils-Nautiloid Canyon Abbott and Cook (2004) Supai Group Transgressional conglomerate: Supai Group Exfoliation joints-Esplanade Sandstone Supai Group, North Canyon, Grand Canyon Exfoliation joints-Esplanade Sandstone Supai Group, North Canyon, Grand Canyon North Canyon String Quartet (photo by F. Cressy) Foreset beds in Esplanade sandstone, Supai Group Coconino Sandstone Hermit Shale Prominent nonmarine units of Grand Canyon Ten Mile Rock - rockfall of Toroweap Formation (marine limestone) Mikey in the tongue of Badger Rapids Kaibab Limestone Crinoid stems-Kaibab Limestone Crinoid stems and ?? fossil-Kaibab Limestone Conodonts? Fish Jaws??-Kaibab Limestone Navajo Sandstone Chinle Formation Moenkopi Formation Chinle Formation Chinle Formation and last-chance flush toilets, Lees Ferry Petrified wood-Chinle Formation (in stream bed behind bathrooms, Lees Ferry) Late Cenozoic Volcanics and Flood Deposits Abbott and Cook (2004) Vulcan’s Throne volcano Blakey, NAU (jan.ucc.nau.edu/~rcb7/Vulcan_Throne.jpg) Lava flow into Grand Canyon Columnar jointing downstream from Lava Falls Basaltic sill upstream from Lava Falls Dike younger than Tapeats Sandstone but older than travertinecemented alluvium Upstream from Lava Falls, Grand Canyon Vulcan’s Anvil volcanic plug-harbinger of doom Lava Falls!! Lava Falls-Cressy expedition Lava Falls-Baron expedition Pumpkin Springs, Grand Canyon travertine Pumpkin Springs, Grand Canyon Grand Canyon Rock Art Whitmore Wash Deer Creek Trail Grand Canyon Artifacts Blacktail Canyon NPS Dig April, 2010 Grand Canyon Artifacts Unkar Delta Grand Canyon Anasazi Structures Unkar Delta Occupied A.D. 850 to A.D. 1200 (NPS) Grand Canyon Anasazi Structures Unkar Delta Grand Canyon Anasazi Structures Nankoweap Granaries Occupied as early as 650 A.D. (Davis et al. (2000) but more likely 1050-1250 A.D. (Schwarz, 1963) Grand Canyon “Ancient Ones” – Cressy Expedition