Igneous Rocks!
Igneous Rock so they are called crystalline Forms when magma cools and becomes solid Are made of crystals… so they are called crystalline
Rock Textures Coarse-grained Fine-grained Cooled very slowly so large crystals could grow Ex – granite Fine-grained Cooled quickly so large crystals did not have time to form Ex - basalt
Other Textures Porphyritic Glassy Vesicular Mixture of small and large crystals Ex - granite Glassy Magma very viscous, cooled quickly Ex - obsidian Vesicular Cooled quickly, full of holes Ex - pumice
Rock Composition Felsic Mafic Intermediate Contains a large amount of silica Usually lighter color Mafic Contains much less silica Usually darker color Intermediate
Rock Structures Intrusive Rock Extrusive Rock Forms underground It is “in” the ground Extrusive Rock Forms on the Earth’s surface It has “exited” the ground
Intrusive Igneous Rock Intrusive rocks cool slower, so their crystals tend to be larger
Intrusive Igneous Rocks
Extrusive Igneous Rock Extrusive rocks tend to cool quicker so the crystals are generally smaller Volcanic Neck
Extrusive Igneous Rock Shiprock, New Mexico
Extrusive Igneous Rock