Chapter 3-Igneous Minerals and Rocks

linked student papers
igneous rocks
          Making Thin Sections- Jill Forsythe (Summer 2003)
          Obsidian- Marciela Cordero (Spring 2008)
          Obsidian Obsession- Stormy Wall  (Spring 2005)
          Pumice Rafts- Daniel Quarto  (Fall 2007)

VOCABULARY

magma

lava

extrusive (volcanic)

intrusive (plutonic)

crystallization

glass

texture

phaneritic

aphanitic

vesicles (gas bubbles)
    (vehicular vesicular basalt assault)

porphyry
    phenocrysts
    groundmass

pyroclastics

Bowen's Reaction Series:

discontinuous series
    olivine (peridot)
    pyroxene (augite)
    amphibole (hornblende)
    biotite (black mica)

continuous series
    calcium plagioclase
    sodium-calcium plagioclase
    calcium-sodium plagioclase
    sodium plagioclase (albite)

residue, low-temperature silicates
    muscovite (white mica)
    quartz
    orthoclase (potassium feldspar)

crystal settling

magmatic differentiation
    gravitational magmatic segregation

assimilation

magma mixing

mafic
    ultramafic

volcanic rocks
    basalt
    andesite
    rhyolite

plutonic rocks
    gabbro
    diorite
    granite

obsidian (volcanic glass- no gas)

pumice (volcanic glass with gas)

pegmatite

tuff and welded tuff

pluton (intrusion)
    discordant
       dike
    concordant
       sill

batholith
laccolith
stock
pipe

columnar jointing
    Devil's Postpile, Calif.

country rock
inclusions (xenoliths)
schlieren
chill zone