Unit Three - Rocks and Minerals - Igneous Rocks Flashcards
What is an Igneous Rock?
(How is it made)
Forms when molten material solidifies
A method to classify igneous rocks is…
Environment of Formation - The LOCATION where liquid rocks solidifies into solid rock
Two types of igneous rocks
Intrusive (Plutonic) Rocks and Extrusive (Volcanic) Rocks
What is a plutonic rock?
An intrusive rock that forms deep within the Earth
What is a volcanic rock?
An extrusive rock formed on Earth’s surface
What is the difference between magma and lava?
Magma is molten rock that is INSIDE of Earth and Lava is molten rock that is OUTSIDE of Earth.
Color
Igneous Rocks
For igneous rocks, color is broken down into two categories - light and dark
Composition
Deifintion and Types of Ignneous
A mixture of minerals and materials that make up the igneous rock
(Mafic and Felsic)
Texture
Defintion
The appearance and characteristics of rocks
Vesicular
Texture consisting of gas pockets that give the appearance of holes
Porphyritic
Texture containing large crystals in a fine grained matrix
What makes a rock vesicular
When an extrusive rock forms, it hardens and cools very quickly, trapping the volcanic gases into the rock. This creates gas pockets, which appears as “holes”.
