Magmatic activity in Brazil linked to one of the Earth's largest mass extinctions

The End-Triassic extinction is one of the largest mass extinctions in the history of Earth. It has been hypothesized that greenhouse gases released from volcanic activity of the Central Atlantic Magmatic Province (CAMP) triggered the extinction. New models in a recent study demonstrate that large-scale gas generation followed the sill emplacement of CAMP in sedimentary basins in northern Brazil.

Supercontinent of Pangea with the The Central Atlantic Magmatic Province in red. Illustration: Research team/CEED

The international research team, including four researchers from CEED (Heimdal, Svensen, Jones Callegaro), modelled that the gas generation from contact metamorphism of carbonates and organic-rich rocks in sedimentary basins in northern Brazil could have included as much as 88,000 gigatonnes CO₂.

The team also performed radiometric dating that confirmed that the sills were emplaced synchronously with the end-Triassic extinction (ETE).

Thea H. Heimdal is the first author of the article in Scientific Reports, Nature. Photo: CEED

The End-Triassic extinction occurred at the end of the Triassic Period (252 million to 201 million years ago). It is believed that 76 percent of all marine and terrestrial species and about 20 percent of all taxonomic families saw their demise in the mass extinctions event.

The new study was recently published in the Nature journal Scientific Reports, January 2018.

Reference:

Thea H. Heimdal, Henrik. H. Svensen, Jahandar Ramezani, Karthik Iyer, Egberto Pereira, René Rodrigues, Morgan T. Jones & Sara Callegaro (2018). Large-scale sill emplacement in Brazil as a trigger for the end-Triassic crisis. Scientific Reports. doi:10.1038/s41598-017-18629-8

Published Feb. 2, 2018 4:54 PM - Last modified Feb. 5, 2018 9:45 AM