scientist have found new evidence that theKT extinction event66 million years ago was a combination of both an asteroid impact and subsequent increase volcanic action . Specifically , they think the Chicxulub shock may have doubled the activity of already present volcanism at the time , at last lead to the extermination of more than 80 % of fauna mintage , including the dinosaurs .
Such a theory has been proposedbefore , but previous estimation propose the impact spark off tonic volcanism . This latest hypothesis suggests a period of volcanism lasting hundreds of M of days was heighten by the encroachment – and those beast that were n’t pass over out in the initial blast were finally wipe out by the drastically changed climate , which include periods of worldwide warming and temperature reduction , and acid rain . The research , conduce by the University of California , Berkeley , is put out in the AAAS journalScience .
“ The fact that volcanism and the impact [ may have ] pass at the same time has been bang for a while , ” study cobalt - author Loÿc Vanderkluysen , from Drexel University in Philadelphia , told IFLScience . “ But we found out that since the eruption started a few hundred thousand years before the impact , the idea that the whole volcanic eruption was triggered by the impact sort of turn a loss ground when the volcanism started before . ”
The scientists came to their conclusion by dating the lava at theDeccan Traps , east of Mumbai in India , which began forming 66 million year ago . They sampled flows from before , during , and after the quenching , using high - preciseness argon-40 / argon-39 isotope dating to contemplate their chronology . result suggested their output replicate within 50,000 years of the asteroid or comet encroachment .
show are the superimposed lava flows of the Deccan Traps , east of Mumbai , India . Mark Richards / UC Berkeley .
Such extremely large volcanic events are estimated to occur every 20 million years , but the luck of the increase in volcanism and the asteroid shock come about at the same time , within 50,000 year , for unrelated intellect is thought to be highly unlikely .
“ The scenario we are evoke – that the wallop triggered the volcanism – does in fact reconcile what had previously appeared to be an unimaginable coincidence , ” said cobalt - author Mark Richards , from the University of California , Berkeley , in astatement .
The location of the impingement and the Deccan Traps were thought to be on opposite slope of the world at the meter , but such was the size of it of the impact effect that every locating on Earth would have experience a magnitude 9 earthquake – enough to set off the increased volcanic bodily process . It ’s potential that volcanic activity in other locations was also intensified .
The exact relationship between the impact and the increase in volcanic activity is not fully known , though . “ The chemical mechanism is not perfectly understood , ” Vanderkluysen distinguish IFLScience . “ This is going to be the arena of next inquiry for us . ” He noted , though , that such result are not unprecedented ; volcanic action in Indonesia in 2006 has been link up to earthquakes in the neighborhood .
This will be the field of future research , and by from better see the relationship between the encroachment and volcanism , the scientist also want to see how organisms on ground and in the ocean were affect otherwise by the upshot .
Image in text : The volcanic region is shown in red , while the researchers took sample from the arena mark by the rectangle . Paul Renne , Berkeley Geochronology Center & UC Berkeley .
