The basic theory of plate tectonics is that along seafloor spreading zones, the continents are separating from one another. As they spread apart, magma comes to the surface and becomes new continental crust. As the tectonic plates move away from spreading zones, they collide with one another.
A stream of river that runs into another stream or river is called a tributary.
e largest of the continents is Asia, which covers about 17.2 million square miles
Hello! Need help on anything?