The velocity of a subducting oceanic slab may vary with time. When it slows down, the overriding plate rolls back and causes the curvature observed. This process can be associated with thrust faults

Some sections of a subducting oceanic slab may be denser than other sections. Where this happens, subduction is slower and at a lower angle causing slower rollback and the curvature observed. This process can be associated with normal faults like in the Caribbean plate

Some sections of a subducting oceanic slab may be denser than others. Where this happens, subduction is faster and steeper causing faster rollback and the curvature observed. This process can be associated with normal faults like in the Caribbean plate

Some sections of a subducting oceanic slab may be denser than others. Where this happens, subduction is slower and at a lower angle causing slower rollback and the curvature observed. This process can lead to development of transform faults like in the Caribbean plate

Some sections of a subducting oceanic slab may be denser than other sections. Where this happens, subduction is faster and steeper causing faster rollback and the curvature observed. This process can lead to development of transform faults like in the Caribbean plate