Subduction zone processes. Cutaway artwork showing the geological processes that occur at a subduction zone between two tectonic plates. An oceanic plate (left) is descending beneath a continental plate (right). At the boundary, mountains are being formed as the rock crumples and is pushed upwards under pressure. New rock is also formed from volcanic eruptions (upper right) as the oceanic plate melts and molten rock rises. This artwork also shows the crumpling of rock strata within the mountains, and ocean floor sediments (brown) being dragged down into the mantle (orange).