Interglacial on snowball Earth

Aug 06, 2012

Researchers from Royal Holloway, University of London have discovered that ice retreated completely through the glaciations.

A team led by Dr Daniel Paul Le Heron from the Department of at Royal Holloway have found evidence revealing the ice was much more dynamic than ever expected on the frozen planet.

Some 715 million years ago, thick ice sheets grew on each continent, as far as the tropics, in an event termed . Glaciers in this icy period have long been thought to be stable throughout the glaciation, with ice acting like a lid for that built up from volcanoes under the ice. Once volcanoes punctured the icy veneer, an unstoppable, catastrophic melt of ice around the globe would occur, and the Earth would warm very rapidly.

Studying spectacular in northern Namibia, where a thick pile of debris was laid down by glaciers, the research team discovered non-glacial shale rocks sandwiched by glacial sediments above and below. Dr Le Heron says “The evidence suggests that ice retreated completely during the glaciation, melting away in a warmer interglacial period, then re-growing before finally disappearing completely. This is a very exciting finding because it shows that these ancient glaciers behaved exactly like ice sheets today”.

The research is published online in Sedimentology.

Explore further: Satellites sees a question mark in Tropical Storm Ana

add to favorites email to friend print save as pdf

Related Stories

Snowball Earth hypothesis challenged

Oct 12, 2011

The hypothesis that the Earth was completely covered in ice 635 million years ago has received a serious blow. The atmospheric concentration of CO2 during that period was much lower than previously thought, ...

Glaciers melting faster than originally thought: study

Apr 04, 2011

(PhysOrg.com) -- A team of scientists from Aberystwyth University, the University of Exeter and Stockholm University, led by Welsh scientist and Professor Neil Glasser, have released at study published in ...

Greenland and Antarctic ice sheet melting, rate unknown

Feb 16, 2009

The Greenland and Antarctica ice sheets are melting, but the amounts that will melt and the time it will take are still unknown, according to Richard Alley, Evan Pugh professor of geosciences, Penn State.

Recommended for you

Operation IceBridge turns five

Oct 17, 2014

In May 2014, two new studies concluded that a section of the land-based West Antarctic ice sheet had reached a point of inevitable collapse. Meanwhile, fresh observations from September 2014 showed sea ice ...

Is Australia's claim to Antarctica at risk?

Oct 17, 2014

While Australia's commitment to a 20-year plan for Antarctica has been welcomed by some it has also raised concerns over the nation's ability to fulfil a credible research role in the south polar region.

User comments : 0