... the Cretaceous-Tertiary boundary (Alvarez et al., 1980) and associated Chicxulub impact crater (Hildebrand et al., 1991) and perhaps recently the Australian Bedout crater (Becker et al., 2004) associated with the Permian- Triassic "great dying" (although ...
... cratering flux early in the stratigraphic sequence of lunar basins but the ... crater density to absolute age, we assumed a constant cratering rate RSPANec ... crater from the density of craters i within it, we used: ti = tNec + ( i - Nec ...
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Ссылки http://www.mso.anu.edu.au/~charley/papers/NormanLineweaver2008.pdf -- 604.5 Кб -- 07.05.2008 Похожие документы
... cratered highlands of the Moon are older than the lunar mare which have a lower ... crater counts of the very old Al-Khwarizmi/King basin to increase along the nearly ...
... magnifying glass to your eye, counting craters on Mercury, volcanos on Mars or ... every square centimetre is covered with craters and debris, created by collisions ... Some must have been huge: there are craters thousands of kilometres across. ...
... We can infer from the dates and sizes of lunar impact craters, whose record goes back to when the Moon formed a solid crust (~4.44 Gyr ago, Sleep et al., 1989) that the surface of the Earth was periodically vaporized and covered with a 2000 K rock vapor ...
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Ссылки http://www.mso.anu.edu.au/~charley/papers/CosmicThermoBiology.pdf -- 201.9 Кб -- 12.05.2003 Похожие документы