Metamorphism

Metamorphism

1. Recrystalisation of a rock due to the increase in pressure and temperature

   • Involves recrystalisation in the solid state without overall chemical change

2. Driving forces for change

   • Temp
     • Pressure
       • Pore fluids
         • Strain
           • Chemisry

3. Rocks are often folded or foliated

4. Isochemical - Chemistry remains the same, just internal reorganisation

   • Metosomatic - Chemistry of the rock changes, minerals lost and introduced

5. Radioactive decay of uranium + potassium from the mantle releases heat

6. Regional metamorphism - increase in pressure an temp

7. Contact metamorphism - increase in temperature

8. Burial/ dynamic metamorphism - increase in pressure

   • Along fault lines such as the San Andreas Fault