Mountains and volcanoes rise along the seam. The process renews the ocean floor and widens the giant basins. A single mid-ocean ridge system connects the world's oceans, making the ridge the ...

Around 10,000 years ago, as the last Ice Age drew to a close, the drifting of the continent of North America, and spreading ...

a mid-ocean ridge that extends along the floor of the Atlantic Ocean southern Europe There are, however, some important exceptions. The Hawaiian Islands, which are entirely volcanic in origin ...