What is the opposing plate involved in the formation of a volcano of the mariana islands?

Collision between Pacific plate and Mariana plate

Explanation:

Due to the collision between the Pacific plate (denser oceanic crust) and Mariana plate (less denser micro-continental crust), the Pacific plate got subducted beneath the Mariana plate, and because of the partial melting of the crust at huge depth, the magma forces to rise up to the surface forming the huge arc of volcanic island .

The trench that is formed due to this collision is known as the Mariana trench and it the deepest trench in the world, where its depth is approximately 11 km. The rock types existing in this area are mainly sedimentary as well as rocks that are produced due to the subsequent volcanic eruptions.

since there isn't any suggested answers i will give you the reason and hopefully you can figure it

south africa, or rather all of africa, has not been in the location in which it is nowadays throughout the geological past. after the super-continent pangaea started to break apart, gondwanaland, in which was africa, moved further south, and parts of it came to be very close to the south pole. because the climate in this part of the world is very cold due to the very dispersed sun rays in there, what is now south africa, started to freeze, and the conditions were right for the formation of glaciers. the glaciers existed up until the period when gondwanaland started to break apart and what is now africa started to move towards north, sp it warmed up and the glaciers melted.