Question

question 9 1 pts which of the following igneous rock textures indicates the fastest cooling rate? fragmental aphanitic glassy porphyritic phaneritic

Explanation:

When magma or lava cools very rapidly, there is not enough time for mineral crystals to form. Glassy igneous rocks form when cooling is so fast that atoms do not have time to arrange into an orderly crystalline structure. Fragmental textures are related to explosive volcanic activity, aphanitic rocks have small - sized crystals from relatively fast but not the fastest cooling, porphyritic rocks have a mix of large and small crystals indicating different cooling rates at different times, and phaneritic rocks have large crystals formed from slow cooling.

Answer:

C. Glassy