- Slides: 12
Igneous Rocks Made from Magma and Lava
Igneous rocks ¬ How are igneous rocks formed? ¬ What do igneous rocks look like? ¬ What do the characteristics tell us about the rock? ¬ What are igneous rocks used for? ¬ How do you use page 6 of the ESRT for Igneous rocks?
Igneous Rocks ¬Rocks that form from solidification of magma or lava (crystallizes)
Texture ¬Intrusive or plutonic - inside the earth’s crust, magma chambers. ¬Large crystals (>1 mm)
Texture ¬ Extrusive or volcanic - lava on the earth’s surface. ¬ Small or no crystals (< 1 mm)
What do igneous rocks look like? ¬ Texture can be glassy, fine grained, coarse grained, or very coarse grained
What do igneous rocks look like? ¬Vesicular = gas bubbles (extrusive) Or ¬Nonvesicular = no gas bubbles
Composition ¬ Felsic light in color and density, rich in aluminum (continental crust) or ¬ Mafic dark in color and high in density, rich in iron and magnesium (ocean crust)
Classification (ID) ¬ Crystals (YES!) ¬ Intrusive or Extrusive – Cooled slowly in the crust = large minerals Intrusive – Cooled rapidly on the surface = no or very small minerals Extrusive – Vesicular = very gaseous lava flow ¬ Color: Light(Felsic) or dark (Mafic)
What are igneous rocks used for?
How to use esrt page 6 - Igneous Rocks?