HONG KONG: It is the debate that has raged ever since the discovery of dinosaurs in the 19th century – just how were they wiped off the face of the planet?
The most popular theory since the 1980s has been that they died after an asteroid strike, but in recent years some scientists have speculated that volcanic eruptions in the Deccan Traps in India may have caused the mass extinction of dinosaurs.
But now a new study from scientists at the University of Leeds has poured cold lava on that theory, and says that the effect of volcanoes on dinosaurs has been over-estimated.
The findings suggest that long-lasting volcanic eruptions called continental flood basalts would probably not have altered global climate enough to trigger a mass extinction.
Dr Anja Schmidt, from the University of Leeds, who led the new research, said: “At the time when the dinosaurs reigned, numerous long-lasting eruptions took place over the course of about a million years. These ‘continental flood basalts’ were not like volcanic eruptions we often see today, with lava gushing from the ground like a curtain of fire.
“Each eruption is likely to have lasted years, even decades, and eruptions were separated by periods without volcanic activity. The lava produced by an eruption of average intensity would have filled 150 Olympic-size swimming pools per minute.”
One common theory was that gases and sulphur from the eruptions filled the atmosphere, stopping sunlight from reaching Earth and dramatically cooling temperatures.