Not just craters, meteorite impact can trigger long-lived volcanic eruptions on Earth

The researchers studied rocks filling one of the largest preserved impact structures on the planet, located in Sudbury, Ontario, Canada. 

By Zee Media Bureau | Updated: May 04, 2017, 16:30 PM IST
Not just craters, meteorite impact can trigger long-lived volcanic eruptions on Earth

New Delhi: A new research has shown that large meteorite impacts cause volcanic eruptions on Earth and not just craters.

The study by an international team, led by geochemists from Trinity College Dublin, showed that large impacts can be followed by intense, long-lived, and explosive volcanic eruptions.

The researchers studied rocks filling one of the largest preserved impact structures on the planet, located in Sudbury, Ontario, Canada.

The meteorite hit Earth 1.85 billion years ago and excavated a deep basin, 1.5 km-thick.

They found rocks that had melted after the impact, as well as volcanic fragments.

The research showed that the composition of the volcanic fragments changed with time.

Right after the impact, volcanism was directly related to melting of Earth's crust. However, with time, volcanism appeared to have been fed by magma coming from deeper levels within Earth.

"This is an important finding, because it means that the magma sourcing the volcanoes was changing with time. The reason for the excitement is that the effect of large impacts on the early Earth could be more serious than previously considered," said Balz Kamber, Professor at Trinity College Dublin in Ireland.

On the early Earth there was a relatively brief period during which roughly 150 very large impacts occurred whereas only a handful have hit Earth since then.

"The intense bombardment of the early Earth had destructive effects on the planet's surface but it may also have brought up material from the planet's interior, which shaped the overall structure of the planet," Kamber said.

The findings, published in the Journal of Geophysical Research: Planets, raise interest in topical research on similar volcanism on other planetary bodies like Mercury, Venus, Mars and the Moon.

(With IANS inputs)