|mhorn||Дата: Thursday, 16.09.2010, 19:29 | Сообщение # 1|
|Schoene B., Guex J., Bartolini A., Schaltegger U., Blackburn T.J. (2010) Correlating the end-Triassic mass extinction and flood basalt volcanism at the 100 ka level // Geology, v. 38; no. 5; p. 387–390. |
Abstract: New high-precision U/Pb geochronology from volcanic ashes shows that the Triassic-Jurassic boundary and end-Triassic biological crisis from two independent marine stratigraphic sections correlate with the onset of terrestrial flood volcanism in the Central Atlantic Magmatic Province to <150 ka. This narrows the correlation between volcanism and mass extinction by an order of magnitude for any such catastrophe in Earth history. We also show that a concomitant drop and rise in sea level and negative δ13C spike in the very latest Triassic occurred locally in <290 ka. Such rapid sea-level fluctuations on a global scale require that global cooling and glaciation were closely associated with the end-Triassic extinction and potentially driven by Central Atlantic Magmatic Province volcanism.
Middle Jurassic - Lower Cretaceous ammonites & aptychi