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End Permian Extinction. Max Zelenevich , Joshua Sung, Andrew Gentoso. Mechanisms. Climate Change. Higher global temperatures Ocean anoxia Ocean temperature rise Sea level change. Ocean Anoxia. Occurred in both shelf and deep sea Higher ocean temperatures Less oxygen
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End Permian Extinction Max Zelenevich, Joshua Sung, Andrew Gentoso
Climate Change • Higher global temperatures • Ocean anoxia • Ocean temperature rise • Sea level change
Ocean Anoxia • Occurred in both shelf and deep sea • Higher ocean temperatures Less oxygen • Less polar-equator temperature anomaly • Ocean current affected • Life not adapted to this • Black shale
Sea Level Change • Rock records alluded to dramatic drop • Would have been below shelves • This not the case • At P-T boundary was dramatic rise
Carbon-13 and Sulfur-34 • Higher Carbon-12 levels in ocean • Results in less productivity • Changes in the circulation • Added organic carbon to system • Increase Sulfur-34
Methane Hydrate • Increase in ocean temperature cause release • Ocean circulation change warmer bottom • Positive feedback • Possible but unlikely mechanism
Volcanism • Siberian traps • Basaltic volcanism • Extremely large • Eruption at P-T boundary • CO2 release • 4,000 km2
Volcanism • Acid Rain • CO2 added to feedback system • Emeishan Flood Basalt
Meteorite Impact • Most craters from Permian era are small • Impact from a meteorite unlikely to cause extinction • Combination of impact and volcanism? • Currently being intensively studied
End Permian Fossil Record http://www.treasure-hunting-team.com/Pictures/Fossil-Fish-1.jpg
Permian Geologic Period • Greater biodiversity than the Triassic • Climate quite varied • Earth still grip of Ice Age after Carboniferous • Organisms • Mollusks, echinoderms, and brachiopods • Trilobites • Amphibians http://www.ucmp.berkeley.edu/permian/permian.html
Triassic Geologic Period • Much less biodiversity • Period of “transition” • 500,000 years to recover • Hot and dry climate • Beginning of evolution to dinosaurs • First flying vertebrates, pterosaurus evolve • Organisms • Early confiers, ginkgos, cycads • Amphibians, some reptiles • Rise of mammals http://www.ucmp.berkeley.edu/mesozoic/triassic/triassic.html
Organisms Hardest Hit • 96% of marine species went extinct • Those attached to sea floor hit hard • Organisms • Corals (rugose and tabulate) • Bryozoans, brachiopods • Trilobites • Tropical foraminifera • 2/3 of terrestrial reptiles and amphibian families • 2/3 of tetrapods lost http://brianlean.files.wordpress.com/2008/08/trilobite1.jpg http://www.museum.state.il.us/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=617&g2_serialNumber=3
What Organisms Fared Better • Detrital feeders (foraminifera) • Anoxic organisms • Some ostracods and foraminifera • Free-swimming organisms (fish, marine chordates) http://www.ucmp.berkeley.edu/arthropoda/crustacea/images/ostracod.jpg
http://www.palaeos.org/images/thumb/9/99/500px-Extinction_intensity.svg.png/300px-500px-Extinction_intensity.svg.pnghttp://www.palaeos.org/images/thumb/9/99/500px-Extinction_intensity.svg.png/300px-500px-Extinction_intensity.svg.png
Absolute dating of the extinction • Absolute dating of volcanic-ash layer in Meishan, Southern China • Lies above many fossils in sedimentary rocks • Lies below paleontological P-Tr boundary • Ash contains zircon and feldspar • Zircon U-Pb dating • Feldspar 40Ar – 39Ar dating • P-Tr boundary ~ 250 Ma http://a21.idata.over-blog.com/600x360/3/02/18/95/actu-8/Actu-9/Actu-10/actu-13/Dossier-14/The-Siberian-Traps-and-the-End-Permian-mass-7.jpg
Ocean Anoxia Record • Marine sediments display anoxia conditions • Sediments enriched with organic matter at P-Tr boundary • Bottom waters had limited oxygen, may have had reducing conditions • Extinction coincided with change from burrowed strata undisturbed strata • Sea bed lost normal complement of bottom-dwelling organisms
Sea level record • Sedimentary rocks show sea-level change • Loss of habitat on shallow continental shelves • Extinction of shelf-dwelling creatures • Record shows low sea level (Permian) • Despite no water locked up polar ice caps • But record more points to rapid sea-level rise before the extinction occurred
Global warming • Significant shifts in temperatures and climate patterns • Humid temperate climate hot, semi-arid climate • 18O/16O record in marine carbonates • Carbon producing organisms incorporated more oxygen-16 than oxygen-18 into shells • Tropical carbonates show a major shift to lighter oxygen correlates with an increased temperature of 6oC (through oxygen isotope record)
Carbon isotope record • At end of Permian, decrease of carbon-13 of 5-6% • Marine carbonates and organic matter from Tethys ocean; marine and animal fossils • Decrease of carbon-13 in carbonates in the ocean because of less productivity in marine organisms • Sediments contained less organic matter • Rapid isotope shifts could be caused by ocean circulation http://www.peripatus.gen.nz/paleontology/lrgBowringetal1998Fig2.gif
SULFUR ISOTOPE RECORD • Sulfur isotope proportion increased • Bacterially mediated sulfate-reduction reactions involve 32S lighter isotope. • Pyrite formation from resulting sulfide enriches the sulfur-32 rather than sulfur-34 • Pyrite generally less of sulfur-34 • Sulfur-34 decreased near end of Permian but rose rapidly when extinction occurred • Could have been achieved by widespread removal of low sulfur-34 material • The formation of pyrite • Fits observation of pyrite in P-Tr boundary http://www.green-planet-solar-energy.com/images/sulfur-bohr.gif
Will It Happen Again? • End-Permian Mass Extinction • Cause: Massive Volcanism • The Ordovician-Silurian Extinction • Cause: Massive Glaciation/Fall in Sea Level • K-T Extinction • Cause: Asteroid Impact
The Ordovician-Silurian Extinction • Background: • 440-450 Million Years Ago • Affected Marine Life Primarily • Greater than 100 marine families went extinct • Causes: • Massive Glaciation • Continent Gondwana shifts over south pole • Global cooling resulted in widespread continental glaciation • Lowered sea level caused reduced Eco space
K-T Extinction • Background: • Occurred 65 million years ago • Killed up to 70% of all plants and animals • Causes: • Large Asteroid Impact • 10 km Asteroid – produced 150 km crater • Rare metals – Iridium (30 times greater) • “Shocked Quartz”
End-Permian Mass Extinction • Background: • Occurred 248-286 million years ago • 90% of marine life went extinct • Significant extinction on land • Life struggled to survive for the next 500,000 years • Believed cause: • Extended volcanic activity lasting more than 500,000 years • Burning of coal • Siberian Traps
End-Permian Mass Extinction • Siberian Traps: • Massive volcanic eruptions in Siberia • Lasted a short period of time ~200,000 years • Huge lava flows “flood basalts” • 1.6 million cubic kilometers of lava • Argon-Argon dating of volcanic layers • Secondary effect of eruption: Burning Coal • Magma intruded into large coal deposits • 3 trillion tons of carbon • Massive methane release • Ocean Acidification • Coal ash inhibits photosynthesis in ocean • Anoxic conditions
Similar Asteroid Impact Occurring Again? • Asteroid 1999 RQ 36 • Possible Impact in year 2182 • Possible mass extinction • 1 in 250,000 chance of impact • Asteroid Apophis close approach in 2029 • Roughly 270 meters across • Pass within 18,300 miles of earth’s surface • www.wired.com/wiredscience/2009/12/closest-asteroid-approach-to-earth/
Future Massive Volcanic Activity • Yellowstone Super Volcano • Lake Toba, Sumatra • Aira, Japan • Lake Taupo, New Zealand • Long Valley, California
Yellowstone Super Volcano • Most recent eruption ~ 70,000 years ago • Super eruption ~ 640,000 years ago • Large eruptions occur roughly every 600,000 to 800,000 years • Caldera bulge (27mi x 30mi) • 10” since 2004 • Magma reservoir • 4-6 miles below surface
End-Permian Mass Extinction Summary • Mass Extinction Due to Volcanic Eruption: • Large releases of sediment/ash and CO2 • Dust blocking sunlight causing collapse of food chain • Large increase in surface temperature • (Runaway Greenhouse Effect) • Burning of coal • Will it happen again? • Possible future asteroid strikes • Volcanic eruptions • When? • Mass Glaciation • Will humans be the cause of the next mass extinction • Increased CO2 levels • Destruction of the ecosystem • Spread of disease
References • Bernard, Emma L. “The Fossil Record of Early Tetrapods: Worker Effort and the End-Permian extinction, p.229-239, 2010 • Allison and Briggs. “Paleoaltitudinal sampling bias, Phanerozoic species and the end-Permian extinction.” 1993 • Chen, Z.Q.; McNamara K.J. “End-Permian extinction and subsequent recovery of the Ophiuroidea”, 2005 • White, Rosalind V. “Earth's Biggest 'Whodunnit': Unravelling the Clues in the Case of the End-Permian Mass Extinction”. P. 2963-2985 • Bowring, Samuel A. “The tempo of mass extinction and recovery: The end-Permian example” , 1990 • Şengör, A. M. Celâl. “The Permian extinction and the Tethys : an exercise in global geology” • Chen, Zhong-Qiaon. “Structural changes of marine communities over the Permian–Triassic transition: Ecologically assessing the end-Permian mass extinction and its aftermath.” p.123-140, 2010. • Sahney, Sarda. “Recovery from the most profound mass extinction of all time.”, http://www.geo.ucalgary.ca/~macrae/timescale/time_scale.gif • C.R. Scotese: Geography of the Earth in the Late Permian. • http://www.ucar.edu/news/releases/2005/images/permian.jpg • http://www.killerinourmidst.com/grafix/P-T%20ocean%20anoxia%201.gif • http://www.nsf.gov/news/news_images.jsp?cntn_id=103190&org=NSF • http://palaeo.gly.bris.ac.uk/palaeofiles/permian/Map.html • Kump, L. R., Pavlov, A. and Arthur, M. A., 2005, Massive release of hydrogen sulfide to the surface ocean and atmosphere during intervals of oceanic anoxia: Geology, v. 33, p. 397-400. • Hotinski, R. M., Bice, K. L., Kump, L. R., Najjar, R. G., and Arthur, M. A., 2001, Ocean stagnation and end-Permian anoxia: Geology, v. 29, p. 7-10. • Grice, K., Cao, C. Q., Love, G. D., Bottcher, M. E., Twitchett, R. J., Grosjean, E., Summons, R. E., Turgeon, S. C., Dunning, W., and Jin, Y. G., 2005, Photic zone euxinia during the Permian-Triassic superanoxic event: Science, v. 307, p. 706-709. • http://www.pbs.org/wgbh/evolution/extinction/dinosaurs/asteroid.html • http://www.classzone.com/books/earth_science/terc/content/investigations/esu801/esu801page03.cfm • http://hoopermuseum.earthsci.carleton.ca//extinction/permcause.html • http://www.semp.us/publications/securitas_reader.php?SecuritasID=40 • http://arstechnica.com/science/news/2011/01/massive-volcanic-eruptions-coal-fires-the-great-dying.ars • http://www.mapsofworld.com/business/industries/coal-energy/world-coal-deposits.html