Post on 03-Jan-2016
EARTH MATERIALSEQ:What are igneous rocks?
An igneous rock is a naturally occurring solid that forms from a hot liquid
mineral assemblage that cools and freezes.
Igneous Rock Primer
CLASSROOMUNSQUARED
Igneous Rock Classification (Identification Key)
COMPOSITION
TEXTURE
Felsic(light color)
Intermediate
Mafic(dark color)
Ultramafic
Large Crystals(Intrusive or Plutonic) Granite Diorite Gabbro
Peridotite
Fine/no Crystals(Extrusive or Volcanic) Rhyolite Andesite Basalt
Large and Fine Crystals Porphyry
Vesicular(Extrusive) Pumice Scoria
Glassy(Extrusive) Obsidian
Fragmented(Extrusive) Tuff
QuartzOrthoclaseNa-plagioclaseMuscovite
Na-Ca plag.Amphibole
Ca-plag.Pyroxene
PyroxeneOlivine
Answers to ID Test1. Felsic intrusive - granite2. Felsic extrusive - rhyolite3. Mafic extrusive - basalt4. Mafic intrusive - gabbro5. Mafic vesicular - scoria6. Mafic glassy - obsidian7. Intermediate intrusive - diorite8. Intermediate extrusive – andesite9. Intermediate fragmented - tuff10. Intermediate int./ext. – porphyry