1. Rocks: Mineral Mixtures
Chapter 4
Rocks: Mineral Mixtures
Chap 4, Sect 2 (Igneous Rock)
Objectives:
Explain how the cooling rate of magma affects the texture of igneous rock.
Distinguish between igneous rock that cools under Earth’s crust and igneous rock that cools on Earth’s surface.

2. Igneous Rock Classifications
2 Ways Igneous Rock Forms:
_______________________Surface of Earth_______________________
Igneous Rock Classifications
Extrusive
Intrusive i

3. Tech Terms: Igneous Rock intrusive 2. extrusive
forms when magma forms when magma
“intrudes” or pushes “exits” or erupts onto
into surrounding Earth’s surface. (fine-
rock UNDER earth’s grained rock that
surface. (coarse cooled quickly)
grained rock that
cooled slowly)
3 geological process form igneous rocks