Life

Volcanoes roiled the Earth at a time when most land was united in one big continent, spewing out roughly 10 million cu. km of lava. Over time, the eruptions split the supercontinent apart and led to the creation of the Atlantic Ocean.

For the study, scientists analyzed rock samples from Nova Scotia, Morocco and outside New York City, all of which came from this once-united landmass, known as the Central Atlantic Magmatic Province.
An analysis of the decay of uranium isotopes in the basalt, a type of rock left by the eruptions, offered researchers more precise dates.
The eruption in Morocco was the earliest, followed by Nova Scotia about 3,000 years later and New Jersey 13,000 years later.

Sediments that lie below that time hold fossils from the Triassic era. Above that layer, they disappear, the study said.
Some of the lost creatures include fish resembling eels, called conodonts, early crocodiles and tree lizards.

“In some ways, the end Triassic extinction is analogous to today,” said lead author Terrence Blackburn, who carried out the study while at the Massachusetts Institute of Technology but is now with the Carnegie Institution.

“It may have operated on a similar time scale. Much insight on the possible future impact of doubling atmospheric carbon dioxide on global temperatures, ocean acidity and life on earth may be gained by studying the geologic record.”

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