By Joe Pinkstone For Mailonline
Published: 12:29 GMT, 2 January 2019 | Updated: 16:00 GMT, 2 January 2019
Scientists claim they could finally have solved the riddle of how a billion years of rock came to be missing from Earth's crust
Researchers have long known about a baffling gap in the geological record, known as the 'Great Unconformity', but until now have struggled to find an explanation as to how it came about.
The Great Unconformity refers to a significant temporal gap in the layers of Earth’s crust between the beginning of the Cambrian period - which started 540 million years ago - and below it, fossil-free crystalline basement rock, which formed about a billion or more years ago.
Now, they believe the missing layer of crust may have been eroded during a hypothesised period of time widely referred to as 'Snowball Earth', when most of the Earth was covered in ice.
Scientists from the University of California now believe they have enough evidence to support their theory that this billion- year period of history may have been ground down by long-standing glaciers before it was washed into the oceans and eventually swallowed into the belly of Earth via the subduction zones between tectonic plates.
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Earth was a frozen sphere of ice around 700 million years ago and the glaciers caused a fifth of the planet's rock to sink into the mantle, claims a new theory (stock)
The Great Unconformity is a significant temporal gap between the formation of the crystalline basement rock and the beginning of the Cambrian period which has never been explained or understood.
It is estimated that this huge discrepancy and loss of rock equated for rock an average of 1.9 to 3.1 miles deep being destroyed.
The theory, published in the journal PNAS, claims up to a third of the Earth's crust was eroded by the ever-moving glaciers of 'Snowball Earth'.
Researchers involved with the study acknowledge the hypothesis needs more research to improve the theory.
'I think, though, we have extraordinary evidence to support that extraordinary