Mid-Ocean Ridges: Fast/Slow Spreading
Fast-Spreading Mid-Ocean Ridge
Faster spreading ridges like the northern and southern East Pacific Rise are “hotter,” meaning more magma is present beneath the ridge axis and more volcanic eruptions occur. Because the plate under the ridge crest is hotter scientists think that the plate responds to the divergent spreading process more fluidly. In simple terms, this means that the ridge spreads more like hot taffy being pulled apart.
Slow-Spreading Mid-Ocean Ridge
Slow spreading ridges like the Mid-Atlantic Ridge generally have large, wide rift valleys, sometimes as big as 10-20 km wide and very rugged terrain at the ridge crest that can have relief of up to a thousand meters (3,128 feet).