Figure 5.10b. Ne-Jd-Ab-Qz Diagram.
Equilibrium assemblages are shown for the 2-component system NaAlSiO4-SiO2 with colored circles for the stable minerals plotted on a composition line. What minerals will be in a rock at equilibrium for the two-component NaAlSi2O6-SiO2 system depends not only on the T and P, but also on the bulk chemical composition of the rock. Select a chemical composition with the slider on the right, then mouse over the T-P diagram to see what minerals will be present and in what proportion for that composition at different temperatures and pressures. The mineral proportions are determined by the lever rule. Click on the "Show MAD" button to show the Mineral Assemblage Diagram for this system. Use the slider to change the bulk composition and the MAD will change when the bulk composition crosses the Jd or Ab composition.
Use the tools available with this diagram to determine what the two chemical reactions are. Then click the "Answer Question" button to return to the Figure 5.10a and submit a new answer.
