Term
|
Definition
Magma is molten rock
– Usually rich in silica and dissolved
gases |
|
|
Term
| How do Igneous Rocks form??? |
|
Definition
Igneous rocks form when magma
cools and solidifies |
|
|
Term
| How do Intrusive Igneous Rocks form??? |
|
Definition
Intrusive igneous rocks form when
magma solidifies underground
• Granite is a common example |
|
|
Term
| How do Extrusive Igneous Rocks form??? |
|
Definition
– Extrusive igneous rocks form when
magma solidifies at the Earth’s
surface (lava)
• Basalt is a common example |
|
|
Term
|
Definition
Texture refers to the size, shape and
arrangement of grains or other constituents
within a rock. |
|
|
Term
| What controls the formation of texture |
|
Definition
Texture of igneous rocks is primarily
controlled by cooling rate |
|
|
Term
| Where do Extrusive Igneous rocks cool, and what is the grain size???? |
|
Definition
Extrusive igneous rocks cool quickly at or
near Earth’s surface and are typically fine-grained
(most crystals <1 mm) |
|
|
Term
| Where do Intrusive Igneous rocks cool, and what is their grain size??? |
|
Definition
Intrusive igneous rocks cool slowly deep
beneath Earth’s surface and are typically
coarse-grained (most crystals >1 mm) |
|
|
