If a back-arc basin is a region related to a subduction zone, how can such an extensional basin form near a boundary defined by compression?
A)Trench rolls back as the old, dense subducting plate sinks.
B)Compression ceases before extension takes over.
C)Rising magma is softening the crust, allowing it to stretch.
D)A plate subducting at an extremely shallow angle is pushing against the back-arc region.

Question

Quizplus · Accepted Answer

In a subduction zone, as the old, dense subducting plate sinks, the trench rolls back, creating a gap between the overriding plate and the subducting plate. This can create extensional forces that lead to the formation of a back-arc basin.

If a Back-Arc Basin Is a Region Related to a Subduction