Key Earth Science Links
End of Permian Extinction—The largest extinction of all time
The Permo-Triassic Extinction, University of Bristol, Department of Earth Sciences. Excellent site with a paleontological overview, evidence for extinction, information concerning the species that went extinct, and good discussions of five theories (volcanism, impact, climate change, formation of the supercontinent, glaciation) for the cause of the mass extinction. Each of the theory sections explains how that theory could cause a mass extinction, what evidence supports the theory, and opposing views to that theory.
When Life Nearly Came to an End , National Geographic. Short description of article about the end-of-Permian extinction, with a picture gallery and a map of the supercontinent Pangea.
Extinction Events. Wikipedia. Online encyclopedia article on extinctions. Good descriptions of the main mass extinctions and possible causes for each, as well as a summary of the evidence for extinction cycles.
The Day the Earth Nearly Died , BBC Science. Summary of the theory that increased vulcanism in the Siberian Traps (the largest volcanic outpouring of all time) and subsequent climate change was the primary cause of the end-of-Permian extinction.
25 years of mass extinctions and impacts: Lucas, S., Geotimes. Easy to read, short discussion of the history of the concept of mass extinctions, followed by summaries of the “Big 5” mass extinctions and their possible causes
Boost to CO2 mass extinction. BBC News. Summary of data suggesting that global warming may have accompanied the end-Permian mass extinction.
Some key references (technical articles)
- Campbell, I.H., Czamaniski, G.K., Fedorenko, V.A., Hall, R.L., and Stepanov, V., 1992, Synchronism of the Siberian Traps and the Permian-Triassic boundary: Science, v. 258, p. 1760-1763. Hypothesizes that SO2 and particulates from Siberian Traps volcanism would have blocked sunlight, led to global cooling, and could have triggered the mass extinction.
- Erwin, D.H., 1990, The end-Permian mass extinction: Annual Review of Ecology and Systematics, v. 21, p. 69-91.Summarizes patterns of diversity in several different families of marine organisms, terrestrial vertebrates, and terrestrial flora at the end of the Permian in order to examine (1) the known changes in the Permian physical environment including sea level, climate, stable isotopes, and geochemical events; (2) possible extinction mechanisms including extra-terrestrial mechanisms, environmental changes, tectonically induced mechanisms, and (3) the evolutionary significance/consequences of this mass extinction.
- Erwin, D. H., 1994, The Permo-Triassic extinction: Nature, v. 367, p.231-236. Identifies three phases to the end-Permian mass extinction, which are linked to multiple events including sea level change, methane gas hydrates, Siberian flood basalts, oceanic anoxia, and climate change. There are nice graphics of sulfur and carbon isotope changes, and sea level, vs. time across the Permian-Triassic boundary, and generic diversity of marine invertebrates across the boundary.
- Erwin, D.H., Bowring, S.A., and Yugan, J., 2002, End-Permian mass extinctions: a review, in Koeberl, C., and MacLeod, K.G., eds., Catastrophic events and mass extinctions: impacts and beyond: Geological Society of America, Special Publication no. 356, p.363-383. Describes middle (ca 260 Ma) and late Permian (ca 251.6 Ma) extinctions. The paper calculates that the late Permian extinction took less than 0.5 million years, and that it coincides with Siberian flood basalt eruptions and marine anoxia. Global cooling and acidization induced by volcanism and marine anoxia are inferred to have been the primary causes of the mass extinction.
- Knoll, A.H., and others, 1996, Comparative earth history and Late Permian mass extinction: Science, v. 273, p. 452-457. This study links carbon isotopic excursions, continental glaciations, and carbonate precipitation to overturn of anoxic deep ocean waters resulting in high CO2 concentrations and extinction.
- Renne, P.R., and others, 1995, Synchrony and causal relations between Permian-Triassic boundary crises and Siberian flood volcanism: Science, v. 269, no. 5229, p. 1413-1416. Infers that Siberian Trap eruptions produced 2 to 3 million cubic kilometers of volcanic ejecta in approximately 1 million years or less based on new age dates of the Siberian Traps.
- Saunders, A., and Reichow, M., 2009, The Siberian Traps and the end-Permian mass extinction: A critical review: Springer-Verlag, Science in China Press, v. 54, no. 1, p. 20-37. Summary of the age dating and timing of Siberian traps volcanism with the end-Permian mass extinction, and the impacts of the largest known flood basalt in history, which include sulfur dioxide, carbon dioxide, climate change, shallow water anoxia, and mass extinction. Includes nice graphics correlating extinction rate with time and major volcanic eruptions; end-Permian CO2 changes, and a schematic diagram of the various influences large-scale volcanism could have had on Permian ecosystems.
- Stanley, S.M., and Yang, X., 1994, A double mass extinction at the end of the Paleozoic: Science, v. 266, p. 1340-1344.Provides data to indicate that the end-Permian extinction consisted of two major mass extinctions separated by ~5 million years. The second and final (Guadalupian event), in which 80% of marine species went extinct, was the most severe biotic crisis of all time.
- Valentine, J.W., and Moores, E.M., 1973, Provinciality and diversity across the Permian-Triassic boundary, in Logan A., and Hills, L.V., eds., The Permian and Triassic Systems and their Mutual Boundary: Canadian Society of Petroleum Geology, Memoir no. 2, p. 759-766. Proposed that continental collision at the end of the Permian and the subsequent closing of seaways caused a drop in sea level of 200 m and led to extinctions of shallow marine organisms.
- White, R.V., 2002, Earth’s biggest “whodunit”: Unraveling the clues in the case of the end-Permian mass extinction: Royal Society, Philosophical transactions: Mathematical, Physical, and Engineering Sciences, v. 360, No. 1801, Astronomy and Earth Science, p. 2963-2985. Good summary of the data or clues to what caused the Permian mass extinction (ocean anoxia, sea-level changes, climatic changes, carbon and sulfur isotope excursions), followed by the possible causes (“perpetrators”) including bad luck, methane hydrate release, volcanism and the Siberian Traps, bolide impact, and the combination of impact and volcanism.
- Wignall, P.B., and Twitchett, R.J., 1996, Oceanic anoxia and the end-Permian mass extinction: Science, v. 272, p. 1155-1158. Suggests that the world's oceans became anoxic at both low and high paleo-latitudes in the Late Permian, which may have been responsible for the end-Permian mass extinction.
Books
- Benton, M.J., 2003, When life nearly died: The greatest mass extinction of all time: New York, Thames and Hudson, 336 p. This book examines the history of the Permian Period, gradualistic vs. catastrophic views of earth history, how the impact theory brought back the catastrophic view, how mass extinctions are determined, the timing of the Permian mass extinction, and the types of life that went extinct. The book evaluates various theories for the Late Permian extinction and discusses the possible modern 6th extinction event.