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End Permian Extinction

End Permian Extinction

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End Permian Extinction

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  1. End Permian Extinction Max Zelenevich, Joshua Sung, Andrew Gentoso

  2. Mechanisms

  3. Climate Change • Higher global temperatures • Ocean anoxia • Ocean temperature rise • Sea level change

  4. 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

  5. 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

  6. 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

  7. Methane Hydrate • Increase in ocean temperature cause release • Ocean circulation change  warmer bottom • Positive feedback • Possible but unlikely mechanism

  8. Volcanism • Siberian traps • Basaltic volcanism • Extremely large • Eruption at P-T boundary • CO2 release • 4,000 km2

  9. http://palaeo.gly.bris.ac.uk/palaeofiles/permian/Map.html

  10. Volcanism • Acid Rain • CO2 added to feedback system • Emeishan Flood Basalt

  11. 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

  12. End Permian Fossil Record http://www.treasure-hunting-team.com/Pictures/Fossil-Fish-1.jpg

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  21. 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)

  22. 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

  23. 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

  24. 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

  25. 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

  26. 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”

  27. 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

  28. 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

  29. 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/

  30. Future Massive Volcanic Activity • Yellowstone Super Volcano • Lake Toba, Sumatra • Aira, Japan • Lake Taupo, New Zealand • Long Valley, California

  31. 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

  32. 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

  33. 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