Journal
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
Volume 440, Issue -, Pages 725-733Publisher
ELSEVIER
DOI: 10.1016/j.palaeo.2015.09.046
Keywords
Acidification; Triassic-Jurassic; Central Atlantic magmatic province (CAMP); Bedded chert; Aeolian dust; Extinction
Funding
- Japan Society for the Promotion of Science [20127767]
- Grants-in-Aid for Scientific Research [26610166, 25400488, 15H02142, 15K17793, 26800266] Funding Source: KAKEN
Ask authors/readers for more resources
The end-Triassic extinction event marks one of the big five mass extinction events of the Phanerozoic. The ultimate cause of the extinction is considered to be volcanic activity at the Central Atlantic magmatic province (CAMP), yet the underlying nature of global environmental changes that accompanied the biotic turnover remains elusive. Here we present chemical and mineralogical studies across the end-Triassic extinction level of the deep-sea chert sequence (Inuyama, Japan). Depleted hematite content normalized by terrigenous material predated the end-Triassic extinction level with significant rock color change from brick red to purple, which is consistent with the rock magnetic records of hematite reported. This suggests the loss of authigenic hematite possibly due to the acidification of bottom-water and the underlying sediment pore-water. This timing is consistent with the initial eruption of CAMP volcanism, suggesting a catastrophic release of greenhouse gases as a cause of deep-ocean acidification. Across the end-Triassic extinction interval, MgO/Al2O3, Fe2O3/Al2O3, and Al2O3/SiO2 increased with change in color from purple to dusty red. This trend became close to those of weathered CAMP basalts in arid area, implying that it became the considerable source of aeolian dust in cherts after the end-Triassic extinction event. These temporal relations support the synchrony among the initial eruption of CAMP, deep-ocean acidification, and the end-Triassic extinction. Similar rock color changes of cherts might have potential information for the volcanisms and deep-ocean acidification in other geologic events. (C) 2015 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available