The researchers used high-resolution seafloor images to study how the structure of the oceanic plate affects deformation in the NW Sumatran region. They found that the highest deformation rates occur at the front of the forearc, near the accretionary wedge. They also observed N-S lineaments on the oceanic plate that influence the shape of thrust anticlines and erosional features. The data suggests that folding in the accretionary wedge is primarily along landward-vergent thrusts, which is uncommon globally. The N-S lineaments play a significant role in shaping the oceanic plate and the deformation in the wedge.