Which process creates new oceanic crust at mid-ocean ridges as continents diverge?

• A. Weathering
• B. Subduction
• C. Glaciation
• D. Seafloor spreading

Answer: (D)

Movement of tectonic plates at divergent boundaries, like mid-ocean ridges, is what creates new oceanic crust. As the two plates pull apart, magma from the mantle rises to fill the gap. When this magma erupts and solidifies, it forms new basaltic oceanic crust, pushing the plates further apart in a process called seafloor spreading. Over time, this adds new crust at the ridge while older crust moves away and can be recycled back into the mantle at subduction zones.

Weathering breaks down existing rocks at the surface, not create new crust. Subduction consumes crust as one plate sinks beneath another. Glaciation relates to ice formation and movement, not the creation of oceanic crust.