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GY 112: Earth History

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GY 112: Earth History UNIVERSITY OF SOUTH ALABAMA GY 112: Earth History Lectures 34 and 35: Cenozoic Overview and Tectonics Instructor: Dr. Douglas W. Haywick Last Time Mesozoic Sedimentation A) Triassic Sedimentation (Breakup of Pangaea) B) Jurassic Sedimentation (Birth of the Atlantic Ocean) C) Cretaceous Sedimentation (Creation of the Coastal Plain Province) D) Mesozoic-Cenozoic climate (Greenhouse-Icehouse Earth Transition) (web notes 32) Mesozoic Sedimentation Triassic •Initial opening of Gulf of Mexico Mesozoic Sedimentation Triassic •Initial opening of Gulf of Mexico Mesozoic Sedimentation Early Jurassic •Initial flooding of Gulf of Mexico and Northern Atlantic Ocean Mesozoic Sedimentation Late-Triassic/Early Jurassic Mesozoic Sedimentation Late Jurassic …major transgression and flooding of the craton begins •Sundance Sea Mesozoic Sedimentation Late Jurassic …major transgression and flooding of the craton begins •Sundance Sea •Clastic wedges Mesozoic Sedimentation Cretaceous •Southern rifting in the Atlantic Ocean •Gulf of Mexico stops opening Mesozoic Sedimentation Cretaceous •Southern rifting in the Atlantic Ocean •Gulf of Mexico stops opening •AL Coastal Plain sedimentation Mesozoic Sedimentation North South Only key formations are labeled (those discussed in GY 112) Mesozoic Climate • Period of high sea level – Associated with rapid sea floor spreading – Long period without reversal Long Cretaceous Normal Chron Cenozoic Climate Paleocene-Middle Eocene: •No circumpolar current Late Eocene-today: •Circumpolar current –Permitted development of glaciers on Antarctica Cenozoic Climate Today’s Agenda A) Cenozoic Overview B) Cenozoic Tectonics 1. More orogenies (Laramide) 2. Western North American tectonic provinces 3. Plateaus and canyons (Web notes 34, 35) Cenozoic Time Frame Era Years Cenozoic (0 to 65 MA) Mesozoic (65 to 245 MA) Paleozoic (245 to 550 MA) Phanerozoic Cenozoic Time Frame USA Period Years The Tertiary and Quaternary Quaternary (1.6 to 0 MA) periods are relicts of an early geological classification of Tertiary (65 to 1.6 MA) Cenozoic time (Primary, Secondary, Tertiary, Quaternary). International Period Years The former divisions were Neogene (24 to 0 MA) soon abandoned. The latter divisions are dropping out of Paleogene (65 to 24 MA) favor. Cenozoic Cenozoic Time Frame Introducing the Epochs (the Period Epoch smallest common divisions Quaternary Holocene (10,000 – 0 years) of geological time) (1.6 - 0 MA) Pleistocene (1,600,000 – 10,000 years) Pliocene (5.0 – 1.6 MA) Tertiary Miocene (24-5.0 MA) (65-1.6Cenozoic Oligocene (37 - 24 MA) MA) Eocene (58- 37 MA) Paleocene (65-58 MA) Key Cenozoic Evolutionary Events Cenozoic Life • Recovery from Cretaceous extinctions – Modern life forms – New animals • Sharks (Megaladons in Plio-Pleistocene) Cenozoic Life • Marine life – Miocene ancestral whales • Sperm whale • Baleen whales • Dolphin – Miocene recovery of planktonic foraminifera Cenozoic Life • Sandy coasts offer new niches – Sand dollars evolved from sea biscuits • Flowering plants expanded – Grasses originated Cenozoic Life • Mammals diversified – Most modern orders present by Early Eocene Cenozoic Life • Bats present by early Eocene Cenozoic Life • Primates evolved in Paleocene – Climbing by Early Eocene Cenozoic Life • Primates modernized in Oligocene – Monkeys – Apelike primates • Aegyptopithecus Cenozoic Life • Mammalian carnivores evolved by mid- Paleogene Cenozoic Life • And diversified soon after... – Saber tooth tiger – Bearlike dogs – Wolflike animals Cenozoic Life • Earliest horses by end of Paleocene – Size of small dogs Cenozoic Life • Early Eocene elephants – Moeritherium • Earliest • Pig sized Cenozoic Life • Mesonychids – Doglike – Size of small bears • Diatrymas – Huge flightless birds – Clawed feet and slicing beaks Cenozoic Life • Few birds with flight – Most waded – No songbirds Cenozoic Life • Oligocene mammals – A few horses in North America – Rhinoceroses • Paraceratherium • Largest land mammal of all time Cenozoic Life • Terrestrial Life – Grasses – Herbs and weeds – Requires arid climate • Cooler climate linked to Antarctic glaciation Cenozoic Life • Spread of C4 grasses – C4 plants • Incorporate more carbon 13 than C3 grasses • Five times more silica – Wears down teeth of grazers Cenozoic Deep Ocean Currents Chalk Board Cenozoic Tectonic Events Cenozoic Tectonic Events •Final breakup of Gondwanna (Australia separated from Antarctica in the Latest Paleocene – earliest Eocene epochs) •India began to collide with Asia forming the Himalayan Mountain Range (Oligocene to Recent) •Africa started to shift northward, gradually sliding under Europe and uplifting the Alps (Oligocene to Recent) •Continued westward movement of North America and South America formed an on again off again land bridge between the two continents. This gave rise to some interesting animal exchanges (see evolutionary events below). •North American orogenies become dominated by strike-slip faulting and uplift. Mountain building in the northern part of the Cordilleran mountains (mostly Canada) slow down stop during the Oligocene. Activity shifts to the southern part of the mountain chain (Colorado, Nevada etc.). •Major late Tertiary flood basalt eruptions occur in Oregon and Washington state. Hot spot volcanism occurs in the area of Yellowstone (Pliocene to present). Composite volcanic eruptions (some incredibly explosive) periodically occurred and still do (e.g., Mt St Helen’s). Cenozoic Tectonic Events •Final breakup of Gondwanna (Australia separated from Antarctica in the Latest Paleocene – earliest Eocene epochs) •India began to collide with Asia forming the Himalayan Mountain Range (Oligocene to Recent) •Africa started to shift northward, gradually sliding under Europe and uplifting the Alps (Oligocene to Recent) •Continued westward movement of North America and South America formed an on again off again land bridge between the two continents. This gave rise to some interesting animal exchanges (see evolutionary events below). •North American orogenies become dominated by strike-slip faulting and uplift. Mountain building in the northern part of the Cordilleran mountains (mostly Canada) slow down stop during the Oligocene. Activity shifts to the southern part of the mountain chain (Colorado, Nevada etc.). •Major late Tertiary flood basalt eruptions occur in Oregon and Washington state. Hot spot volcanism occurs in the area of Yellowstone (Pliocene to present). Composite volcanic eruptions (some incredibly explosive) periodically occurred and still do (e.g., Mt St Helen’s). Cenozoic Tectonic Events •Final breakup of Gondwanna (Australia separated from Antarctica in the Latest Paleocene – earliest Eocene epochs) •India began to collide with Asia forming the Himalayan Mountain Range (Oligocene to Recent) •Africa started to shift northward, gradually sliding under Europe and uplifting the Alps (Oligocene to Recent) •Continued westward movement of North America and South America formed an on again off again land bridge between the two continents. This gave rise to some interesting animal exchanges . •North American orogenies become dominated by strike-slip faulting and uplift. Mountain building in the northern part of the Cordilleran mountains (mostly Canada) slow down stop during the Oligocene. Activity shifts to the southern part of the mountain chain (Colorado, Nevada etc.). •Major late Tertiary flood basalt eruptions occur in Oregon and Washington state. Hot spot volcanism occurs in the area of Yellowstone (Pliocene to present). Composite volcanic eruptions (some incredibly explosive) periodically occurred and still do (e.g., Mt St Helen’s). Cenozoic Tectonic Events •Final breakup of Gondwanna (Australia separated from Antarctica in the Latest Paleocene – earliest Eocene epochs) •India began to collide with Asia forming the Himalayan Mountain Range (Oligocene to Recent) •Africa started to shift northward, gradually sliding under Europe and uplifting the Alps (Oligocene to Recent) •Continued westward movement of North America and South America formed an on again off again land bridge between the two continents. This gave rise to some interesting animal exchanges (see evolutionary events below). •North American orogenies become dominated by strike-slip faulting and uplift. Mountain building in the northern part of the Cordilleran mountains (mostly Canada) slow down stop during the Oligocene. Activity shifts to the southern part of the mountain chain (Colorado, Nevada etc.). •Major late Tertiary flood basalt eruptions occur in Oregon and Washington state. Hot spot volcanism occurs in the area of Yellowstone (Pliocene to present). Composite volcanic eruptions (some incredibly explosive) periodically occurred and still do (e.g., Mt St Helen’s). Cenozoic Tectonic Events •Final breakup of Gondwanna (Australia separated from Antarctica in the Latest Paleocene – earliest Eocene epochs) •India began to collide with Asia forming the Himalayan Mountain Range (Oligocene to Recent) •Africa started to shift northward, gradually sliding under Europe and uplifting the Alps (Oligocene to Recent) •Continued westward movement of North America and South America formed an on again off again land bridge between the two continents. This gave rise to some interesting animal exchanges (see evolutionary events below). •North American orogenies become dominated by strike-slip faulting and uplift. Mountain building in the northern part of the Cordilleran mountains (mostly Canada) slows down stop during the Oligocene. Activity shifts to the southern part of the
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