GEO Final

• The Acadian orogeny is the Devonian orogeny associated with the east coast of Laurentia
• The acadian orogeny was caused by a catskill wedge of river sandstone, conglomerates, and floodplain mudstones.
• Shale is the dominate strata in ohio during the devonian
• anoxia associated with the delivery of large quantities of plant detritus to the oceans is the primary cause of the late devonian mass extinction
• the alleghanian orogeny occured on the east coast of laurentia at the Mississippian pennsylvanian boundary. This was a continent continent collision
• Cyclotherms are repetitive marine/nonmarine deposition caused by growth and melting of polar ice sheets
• clastic deposition is important in the pennsylvanian period. plants led to coal.
• Carbonate reefs capped by evaporites are the form of deposition in the delaware and midland basins of west texas
• the main cause of terminal permian mass extinction is intense global warming due to extensive volcanism of siberian traps
• nevadan orogeny --> sevier orogeny --> laramide orogeny
• the three mesozoic orogenys are all oceanic-continental subduction with eastwards subduction
• Servier orogeny can be described as thin skinned tectonics
• laramide orogeny can be described as thick skin tectonics
• pangea began to break apart in the triassic
• the warmest time in earths history was the cretaceous
• the final marine regression from the western interior was during the cretaceous
• the main cause of the cretaceous mass extinction was an asteroid impact
• The cretaceous mass extinction could also be caused by the decan traps and extensive volcanism in india
• the cretaceous mass extinction occured around 66 mya
• during the cretaceous mass extinction dinosaurs went extinct
• scleratinian corals are the dominant reef builders in the triassic
• the dominant reef builder today is scleratinian corals
• crinoids were at their peak diversity during the Mississippian period
• The devonian was the age of the fish
• the first reptiles appeared during the pennsylvanian period
• dinosaurs lived from the late triassic to the cretaceous
• the first large forests appeared during the devonian period
• cycads were the dominant trees in the jurassic
• the first flowering plants appeared in the cretaceous
• the pleistocene epoch ranged from 2.6 million to 10,000 years ago
• wobble of axis - 20,000 years
• change in tilt of axis - 40,000 years
• change in orbit around sun - 100,000 years
• the pleistocene glacial/interglacial cycles appear to sclae with the combined effects of all three milankovitch cycles and the 100,000 year milankovitch cycle.
• Mechanisms for long term cooling:

  • The artic oceans being nearly land locked: this restricts warm water from entering near the pole areas
  • South pole has been covered by continent since 23 million years ago: this effects reflectivity and heat absorption becuase continents are good reflectors of solar radiation.
• cambrian --> ordovican --> silurian --> devonian --> mississippian --> pennsylvanian --> permian