Final answer:
Yes, plutonic rocks are the same as intrusive rocks; both form from magma cooling slowly beneath the Earth's surface, resulting in a coarse-grained texture such as seen in granite.
Step-by-step explanation:
Plutonic rocks are indeed the same as intrusive rocks. These rocks are formed from magma that cools and solidifies beneath the surface of the Earth. This process occurs over thousands to millions of years, allowing large crystals to form, creating a coarse-grained texture. This is in contrast to extrusive rocks, which form from lava that cools quickly on the Earth's surface, resulting in fine-grained rocks.A common example of a plutonic rock is granite, which is composed mainly of light-colored minerals and has a coarse-grained texture. The identification of plutonic rocks is based on the mineral composition and the size of the crystals within the rock. This understanding is significant when evaluating geological provinces because plutonic rocks, with their slow cooling ages, reveal the history of the Earth’s interior processes distinct from the history told by extrusive volcanic rocks.In conclusion, the terms plutonic and intrusive are interchangeable and refer to the same type of igneous rocks that form deep within the Earth, characterized by their coarse-grained structure due to the slow cooling of magma.