Nature Study Links 1 Billion-Year Rock Gap to Mantle Upheaval
Updated
Updated · Ars Technica · Nov 6
Nature Study Links 1 Billion-Year Rock Gap to Mantle Upheaval
3 articles · Updated · Ars Technica · Nov 6
Summary
New models in Nature argue Earth’s mantle helped create the Great Unconformity, a geologic gap that can exceed 1 billion years and is starkly exposed in the Grand Canyon.
Hundreds of millions of years of slow mantle flow likely lifted continents, exposing them to intense erosion before subsidence let younger sediments bury the surface.
Glaciation still plays a central role: between about 720 million and 635 million years ago, tropical-reaching ice sheets could have scoured uplifted land roughly 10 times more effectively than rivers.
The mechanism may explain why the unconformity is widespread in North America and appears in parts of northern Europe and northern China, rather than being truly global as a full Snowball Earth scenario might suggest.