1. Composition of Igneous Rock Joy C. Villaraza

2. 1.Composition A.) Sialic or Felsic B.) Intermediate C.) Mafic D.) Ultramafic 2. Refferences

3. Composition of Igneous rocks Chemical composition Chemical composition Color or minerals Color or minerals

4. Sialic or granitic or felsic Dominated by silicon and aluminum (SiAl) Dominated by silicon and aluminum (SiAl) Light in color Light in color Forms a stiff (viscous) lava or magma Forms a stiff (viscous) lava or magma Granite Rhyolite

5. Intermediate (or andesitic) Composition between sialic and mafic Composition between sialic and mafic Andesite(aphanitic) Andesite(aphanitic) Doirite(phaneritic) Doirite(phaneritic)

6. Mafic (or basaltic) Contains abundant ferromagnesian minerals (magnesium and silicates) Contains abundant ferromagnesian minerals (magnesium and silicates) Dark in color (dark gray to black) Dark in color (dark gray to black) Forms a runny (low viscosity) lava Forms a runny (low viscosity) lava Basalt Basalt gabbro gabbro

7. Ultramafic Almost entirely magnesium and iron silicates (ferromagnesian minerals) Almost entirely magnesium and iron silicates (ferromagnesian minerals) Commonly found as xenoliths in basaltic lavas Commonly found as xenoliths in basaltic lavas Peridotite(phaneritic) Peridotite(phaneritic)

8. Igneous Rock Composition Chart FelsicIntermediateMafic

9. Bowen’s Reactions Bowen’s Reactions characterize the process of crystallization magma. characterize the process of crystallization magma. differentiation as magma cools differentiation as magma cools

11. http://hyperphysics.phy-astr.gsu.edu/hbase/geophys/mincomp.html http://facweb.bhc.edu/academics/science/harwoodr/Geol101/labs/igneous/Text ure.htm#Phaneritic http://www.gpc.edu/~pgore/geology/geo101/igneous.htm