Unconformity between the metamorphic Proterozoic basement complex and ... that large amounts of mass erosion matched with the Snowball Earth period. "The new research verifies and advances the ...

The Proterozoic Eon, spanning from 2,500 million to 539 ... when Earth experienced two severe glaciations known as Snowball Earth events. These ice ages, occurring between 720 and 635 million ...