1. Magma

2. Composition of Magma
Slushy mix of molten rock, gases, and mineral crystals
Elements in magma include:
Oxygen, Silicon, Aluminum, Iron, Magnesium, Calcium, Potassium, and Sodium.
Most abundant molecule is Silica.

3. Formation of Magma
Temperature, Pressure, water content and mineral composition effect magma formation.
In the laboratory most rocks melt between degrees Celsius.
Increasing pressure raises the melting point
Increasing water content lowers the melting point.

4. Types of magma Basaltic Magma
Formed in upper mantle, low silica and gas content, low viscosity.
Andesitic Magma
Formed when oceanic crust is subducted into mantle, medium silica and gas content, intermediate viscosity.
Rhyolitic Magma
Formed when molten rock mixes with silica and water rich continental crust, high viscosity, large volume of trapped gases.

5. Basaltic Lava

6. Andesitic Lava

7. Rhyolitic Lava

8. Viscosity Internal resistance to flow.
Ex. Honey, liquid soap, motor oil have higher viscosity than water, vinegar or gasoline.