13.8k views
17 votes
What is the difference between an intrusion and extrusion?

User Jcaliz
by
3.4k points

2 Answers

13 votes
Extrusive rocks are formed on the surface of the Earth from lava, which is magma that has emerged from underground. Intrusive rocks are formed from magma that cools and solidifies within the crust of the planet
User Ergin
by
3.4k points
12 votes
An intrusion is any body of intrusive igneous rock, formed from magma that cools and solidifies within the crust of the planet. In contrast, an extrusion consists of extrusive rock, formed above the surface of the crust.
User Intensivist
by
3.5k points