CRYSTALLIZATION IN BINARY SYSTEMS

We will examine four separate binary systems which are pertinent to igneous petrology. With each of the systems examined we will consider:

  1. EQUILIBRIUM CRYSTALLIZATION - where the liquid and crystals remain in contact with each other, and there is no change in the bulk chemical composition as a result of crystallization.
  2. FRACTIONAL CRYSTALLIZATION - where the liquid and crystals do not remain in contact, the crystals are prevented from reacting with the liquid. The final liquid composition is not the same as the initial bulk chemical composition.