The biggest design innovation that SpaceX has pioneered is, of course, the fact that Dragon 2 is partially reusable, potentially resulting in a significant cost reduction. The first stage of the spacecraft is capable of re-entering the atmosphere and landing vertically after separating from the second stage.
At some convergent boundaries, an oceanic plate collides with a continental plate. Oceanic crust tends to be denser and thinner than continental crust, so the denser oceanic crust gets bent and pulled under, or subducted, beneath the lighter and thicker continental crust. This forms what is called a subduction zone.
It is the source of the nation's petroleum deposits.
