The Peninsular terrane is now part of the crust of North America in southern Alaska.The dominant rock type in this terrane is intrusive igneous rock that ranges in composition from gabbro to granite and volcanic rock with a similar compositional range.Geologic evidence indicates the Peninsular terrane collided with North America during late Mesozoic time.Which of the following would be the most reasonable interpretation for the origins of the Peninsular terrane?

Question

Quizplus · Accepted Answer

The dominant rock type in the Peninsular terrane is consistent with an island arc origin, which typically consists of volcanic and intrusive igneous rocks. The collision with North America during late Mesozoic time also supports the idea of an island arc being accreted to the continent.

The Peninsular Terrane Is Now Part of the Crust of North