What types of rocks occur at subduction zones and why?

At subduction zones, primarily volcanic rocks, such as andesite and basalt, occur due to the melting of the subducted oceanic plate and the overlying mantle material. As the oceanic plate descends, it releases water and other volatiles, which lower the melting point of surrounding rocks, leading to magma formation. Additionally, sedimentary rocks from the subducting plate can also be metamorphosed under high pressure and temperature conditions, resulting in various metamorphic rocks. This dynamic process contributes to the formation of volcanic arcs and mountain ranges associated with subduction zones.