The curving line of earthquakes near the center of the Atlantic Ocean is a reflection of the Mid-Atlantic Ridge, a linear zone whree new crust is formed as molten rock ascends to the Earth's surface. This process has formed one of the Earth's longest mountain ranges, which, except for in Iceland and a few other small islands, is mostly unseen beneath the sea surface. Compare the relative shape of the Mid-Atlantic Ridge with the coasts of North and Sount America and the costs of Europe and Africa. Their puzzle-like shapes have resulted from the separation and spreading of these continents away from the Mid-Atlantic Ridge.
