What is still unknown is the actual process
A team of geophysicists from the University of California, Berkeley think they have the answer
When that asteroid slammed into planet earth it probably rang the Earth like a bell, triggering volcanic eruptions around the globe which in turn contributed to massive scale of devastation everywhere on Earth
The timeline of the most immense eruptions of lava in India which is known as the Deccan Traps fell "uncomfortably close" to when the impact happened
"If you try to explain why the largest impact we know of in the last billion years happened within 100,000 years of these massive lava flows at Deccan
While the Deccan lava flows, which started before the impact but erupted for several hundred thousand years after re-ignition, probably spewed enormous amounts of carbon dioxide and other noxious, climate-modifying gases into the atmosphere
Richards proposed in 1989 that plumes of hot rock, called "plume heads," rise through Earth's mantle every 20-30 million years and generate huge lava flows, called flood basalts, like the Deccan Traps. It struck him as more than coincidence that the last four of the six known mass extinctions of life occurred at the same time as one of these massive eruptions
"Paul Renne's group at Berkeley showed years ago that the Central Atlantic Magmatic Province is associated with the mass extinction at the Triassic/Jurassic boundary 200 million years ago, and the Siberian Traps are associated with the end Permian extinction 250 million years ago, and now we also know that a big volcanic eruption in China called the Emeishan Traps is associated with the end-Guadalupian extinction 260 million years ago," Richards said
"It's inconceivable that the impact could have melted a whole lot of rock away from the impact site itself, but if you had a system that already had magma and you gave it a little extra kick, it could produce a big eruption," said Michael Manga, a professor in the UC Berkeley Department of Earth and Planetary Science
Similarly, Deccan lava from before the impact is chemically different from that after the impact, indicating a faster rise to the surface after the impact, while the pattern of dikes from which the supercharged lava flowed
"There is a profound break in the style of eruptions and the volume and composition of the eruptions," said Paul Renne, a professor in residence in the UC Berkeley Department of Earth and Planetary Science and director of the Berkeley Geochronology Center. "The whole question is, 'Is that discontinuity synchronous with the impact?'
Richards, Renne and graduate student Courtney Sprain, along with Deccan volcanology experts Steven Self and Loyc Vanderkluysen, visited India in April 2014 to obtain lava samples for dating, and noticed that there are pronounced weathering surfaces, or terraces, marking the onset of the huge Wai subgroup flows
Geological evidence suggests that these terraces may signal a period of quiescence in Deccan volcanism prior to the Chicxulub impact. Apparently never before noticed, these terraces are part of the western Ghats, a mountain chain named after the Hindu word for "Steps"
"This was an existing massive volcanic system that had been there probably several million years, and the impact gave this thing a shake and it mobilized a huge amount of magma over a short amount of time," Richards said
"The beauty of this theory is that it is very testable, because it predicts that you should have the impact and the beginning of the extinction, and within 100,000 years or so you should have these massive eruptions coming out, which is about how long it might take for the magma to reach the surface"
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