A large chunk of the Earth's crust is missing, but scientists have now discovered where it is.
The world is constantly asking scientists strange questions, with new technology like space imagery helping them solve mysteries such as water "signs" left on the Earth's surface.
Another mystery that baffled experts for more than a century was known as the "Great Unconformity" and referred to large slabs of the Earth's crust that were missing from the geological record.
New evidence has revealed that their extinction may have been due to severe glacial erosion that occurred during a time known as the "Snowball Earth," when almost the entire planet was covered in ice.
The result is a gap in the sedimentary record that occurs when the age of rocks changes significantly due to erosion of earlier rock, which is then replaced by younger rock.
The phenomenon was observed in 1869 in the Grand Canyon in Arizona. Experts noticed that the age of the rocks changed significantly and found that this was repeated in several places around the world, giving it the name The Great Unconformity.
The authors of one study were able to calculate that a global average of 3-5 kilometers (2-3 miles) of rocks were removed due to glacial erosion, leaving them "missing" from the data.
The study's lead author, Dr. Brenhin Keller of the Berkeley Geochronology Center, explained that the rate of rock loss is enormous, estimating, along with his colleagues, that a billion cubic kilometers (200 million cubic miles) of Pre-Cambrian material is missing based on what was expected to exist.
Their theory suggests that there was much more erosion before the start of the Phanerozoic era than experts initially thought, and they presented evidence showing that crystals from that era have isotopes of hafnium and oxygen.
These isotypes are consistent with weathering from older rocks and deposition at low temperatures. Their theory also suggests that this is why there are so many asteroid craters less than 700 million years old, and only two dated to be older than that.
As for the current location of the rock, it is argued that glaciers that eroded the sedimentary rocks also washed them into the sea.
(AA/BalkanWeb)
