What causes igneous rocks to become metamorphic rocks? Earth Science Rocks Igneous Rocks 1 Answer Suryin =) Nov 20, 2015 high temperatures and pressures Answer link Related questions What is basalt? How are intrusive igneous rocks formed? How does crystal size relate to how long the rock took to cool? What is obsidian? What are some types of intrusive igneous rocks? What is rhyolite? What is granite? How are igneous rocks classified and differentiated from each other? Why igneous rocks are hard? Why do igneous rocks have crystals? See all questions in Igneous Rocks Impact of this question 2081 views around the world You can reuse this answer Creative Commons License