Greenland is the largest island on earth  It was formed 3 8 billion years ago  Most of the area is covered by ice and snow  There are a large number of ancient rock fossils buried in the ground of Greenland  They are arranged like a neat dyke, also known as serpentine
Serpentine is a kind of rock formed by squeezing the seabed continent when two continental plates collide with each other in motion.
 Through these serpentines, one can conclude that Greenland may have been a submarine continent in ancient times