Chemostratigraphic evidence of Deccan volcanism from the marine osmium isotope record.
Continental flood basalt (CFB) volcanism is hypothesized to have played a causative role in global climate change and mass extinctions. Uncertainties associated with radiometric dating preclude a clear chronological assessment of the environmental consequences of CFB volcanism. Our results document a 25% decline in the marine 187Os/188Os record that predates the Cretaceous-Tertiary boundary (KTB) and coincides with late Maastrichtian warming. We argue that this decline provides a chemostratigraphic marker of Deccan volcanism and thus constitutes compelling evidence that the main environmental consequence of Deccan volcanism was a transient global warming event of 3 degrees to 5 degrees C that is fully resolved from the KTB mass extinction.
Ravizza
G
G
Department of Geology and Geophysics, University of Hawaii, Honolulu, HI 96822-2225, USA. ravizza@hawaii.edu
Peucker-Ehrenbrink
B
B
D000818:Animals; D002980:Climate; D019015:Geologic Sediments / Q000737:chemistry*; D017752:Greenhouse Effect; D007554:Isotopes; D009992:Osmium / Q000032:analysis*; D011156:Population Density; D012623:Seawater / Q000737:chemistry; D013995:Time; D018707:Volcanic Eruptions
D007554:Isotopes; D009992:Osmium