xPlate tectonics : The theory supported by a wide range of evidence that considers the Earth's crust and upper mantle to be composed of several large, thin, relatively rigid plates that move relative to one another.
There used to be sea ice floating on the tropical ocean, according to new evidence found by geologists. This was quite a long time ago, 716.5 million years ago, during a time known as Snowball Earth. This...Read more