It was not a meteor strike that wiped out dinosaurs from the earth, but intense volcanic activities in the Deccan region.
Marine sediment from the Krishna-Godavari basin near Rajahmundry has helped scientists solve the age-old mystery of the disappearance of dinosaurs and most other life on earth 65 million years ago.
A team of scientists from USA and India collected samples of dead plankton (micro-organisms) from the oil wells of the Oil and Natural Gas Commission in the KG Basin and subjected them to paleontological studies. The results showed that dinosaurs and other animals were wiped out of the earth, not because of a single meteor strike, but due to intense volcanic activity in the Deccan region.
There were at least three major volcano eruptions in the Deccan, which led to intense flow of lava, dust and poisonous gases like carbon dioxide and sulphur dioxide. The gases enveloped the earth killing a majority of animals including the giant reptiles.
The volcanic eruption had an impact right till present-day Mumbai and Hyder-abad to Rajahmundry and downward. The Indo-US team comprised Dr Gerta Keller of Princeton University and P.K. Bhowmick, H. Upadhyay, A. Dave, A.N. Reddy and B.C. Jaiprakash, of the ONGC.
The researchers collected the plankton from the sediment trapped in the Deccan lava flows, the largest flows on earth, near Rajahmundry.
After studies, they rejected the prevailing theory that the extinction of dinosaurs was caused by a single large meteorite.
Plankton population plummeted
Dr Gerta Keller of Princeton University said, “Marine sediments from Deccan lava flows show that the population of a plankton species widely used to gauge the fallout of prehistoric catastrophes plummeted nearly 100 per cent in the thousands of years leading up to the mass extinction.”
“Our work provides the first one-to-one correlation between the mass extinction and Deccan volcanism,” she added.
The marine sediments preserved between lava flows from the second and third phase eruptions contained evidence of the KT (Cretaceous-Tertiary) boundary, a thin, worldwide geological layer that marks the mass-extinction event. The activity wiped out nearly 100 per cent of planktonic foraminifera.
