Asteroid and Comet Impacts
The impact of an extraterrestrial object (either an asteroid or comet) with the Earth’s surface.
There are now over 170 asteroid and comet impact craters that have been identified on the surface of the Earth (Table 1). These craters represent a small subset of the total impacts that have occurred during the history of life. Today, impact craters probably represent something on the order of 50,000 km 2of Earth’s surface. Although this is a small habitat area, impacts are the only extraterrestrial mechanism capable of causing localized ecological disturbance. Because impacts are a mechanism capable of delivering a pulse of energy into ecosystems, from a geobiological point of view they present an important addition to the overall picture of how ecosystems are disturbed and how they recover through time. Comparison to other processes involving ecological disturbance and recovery including volcanism, glaciation/deglaciation, storm damage, fire, landslides, and...
KeywordsImpact Event Impact Crater Shock Pressure Thermal Pulse Pore Collapse
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
- Cremer, H., and Wagner, B., 2003. The diatom flora in the ultra-oligotrophic Lake El’gygytgyn, Chukotka. Polar Biology, 26, 105–114.Google Scholar
- Melosh, H. J., 1989. Impact Cratering: A Geologic Process. Oxford: Oxford University Press.Google Scholar
- Schoeman, F. R., and Ashton, P. J., 1982. The diatom flora of the Pretoria Salt Pan, Transvaal, Republic of South Africa. Bacillaria, 5, 63–99.Google Scholar
- Smelror, M., Dypvik, H., and Mørk, A., 2002. Phytoplankton blooms in the Jurassic-cretaceous boundary beds of the Barents Sea possibly induced by the Mjølnir impact. In Buffetaut, E., and Koeberl, C. (eds.), Geological and Biological Effects of Impact Events. New York: Springer-Verlag, pp. 69–83.CrossRefGoogle Scholar
© Springer Science+Business Media B.V. 2011