Question

Based on texture, how would you distinguish extrusive igneous rocks from intrusive igneous rocks? Include at least three factors that contribute to igneous rock textures and any textural clues that can be seen in igneous rocks.

Answer 1

Answer:The texture of igneous rock is primarily controlled by it's cooling rate.

Explanation:extrusive igneous rock cool quickly at or near the earth surface and they are typically fine grained , while intrusive ignoeus rock cools slowly deep inside the earth surface and are coarse grained .the factors that contribute to igneous rock texture are : (a) viscosity of the magma

(b) rate of cooling

(c) the relative rate of growth of the constituent minerals.

The textural clue that can be seen on an igneous rock is how large the individual mineral grain is in the final solid rock