Running along the top of this chain of mountains is a deep crack, called a rift valley. It is here that new ocean floor is continuously created. As the two sides of the mountain move away from ...

As well as the basalt that is erupted into the valley and injected into the rocks below to create new ocean floor, sedimentary rocks will also be deposited within the rift valley. At first the rift ...

What made the discovery even more startling was the central valley, which Tharp believed was a rift—a place where the ocean ...