How wide is the rift valley along the crest of the Mid-Atlantic Ridge?

The rift valley running along the crest of the Mid-Atlantic Ridge is approximately 50 to 75 miles (80 to 120 km) wide.1

While general geological classifications for slow-spreading ridges often cite a typical rift valley width of 20 to 40 km (about 12 to 25 miles), the specific valley associated with the Mid-Atlantic Ridge is documented as being wider. This rift valley serves as the zone of seafloor spreading, where magma from beneath the Earth's crust wells up to create new oceanic crust.213