In this image we can see the Cordilleran fold and thrust belt in Canada. Some have described the structural form of arc environments using the following unique terminology. The accretionary wedge is called the ‘Synthetic Thrust Belt,’ where the direction of shear on the down-going plate is the same as the direction of shear within the wedge. The fold and thrust belt in back arc is referred to as the ‘Antithetic Thrust Belt’ because the direction of the shear is opposite to the direction of shear in the subduction zone. Here is a cross section of the antithetic thrust belt in Canada that involves the Paleozoic sediments of the passive margin and young Mesozoic sediments. Courtesy of Prof. Burchfiel.