Fo
Liquid
En
SiO2 
Forsterite + Enstatite
Enstatite + Silica
Enstatite + Liquid
Forsterite + Liquid
Text Box: Temperature
Temperature
P = 1 atm
1. Cool Z to liquidus;
2. Removal of Fo causes L to change composition
3. L reaches peritectic, P; Fo reacts with L to form En
P
E
4. L is consumed in reaction
5. Fo + En cool
Z
Fo crystallizes