"Snowball Earth" May Have Been Caused By The Start Of Plate Tectonics
Science says that about 700 million years ago the Earth was covered from pole to pole in a massive amount of ice and snow. This period is called "Snowball Earth" by scientists and a wealth of theories have surfaced over the years to explain what might have caused this to happen. The latest theory suggests that the root cause of Snowball Earth could have been a cracking crust at the beginning of plate tectonics.
Plate tectonics is the movement of the Earth's crust, the same phenomenon causes earthquakes. The Earth is the only known body in the solar system to have plate tectonics where the lithosphere is fragmented like pieces of a puzzle with each piece able to move independently. Scientists say that it is much more common for planets to have a single, unfragmented, outer shell known as "Single Lid Tectonics."
There is no way for science to know exactly when the crust of the Earth broke up into plates, but the consensus is that this happened between 3 and 3.5 billion years ago. This new study proposes a more recent transition to plate tectonics between 800 and 600 million years ago in the mid-Neoproterozoic era. Scientists from the University of Texas say that geological features linked to plate tectonics only date back that far.
The scientists say that the Earth's crust cracking would have been a cataclysmic event and had global repercussions, they believe those repercussions were Snowball Earth. As it happens, Snowball Earth matches up exactly with this new timeframe for plate tectonics. Other theories about what led to the massive cooling number 22 and the scientists in this new study believe that plate tectonics kicking off could have been the root cause of all those scenarios.
The other 22 hypotheses about Snowball Earth's cause include things like volcanic eruption, changes to Earth's rotational axis, and rocks locking away carbon dioxide. The scientists do note that this theory goes against conventional thinking and needs to be examined further.
SOURCE: New Atlas