Figure 1.13. MORB basalt experimental phase diagram.Diagram of the olivine-plagioclase-quartz-augite quarternary system, projected from the plane of plagioclase saturation onto the plane Olivine-quartz-augite (after Walker and others, 1979. System is plotted in mole components. Points A and B are starting compositions referred to in the text. Point P is a peritectic point in this system while Point E is a eutectic point. Note that since this publication of this diagram refined (and slightly more complex) phase-relations have been determined for this system and published (see Grove and Bryan, 1983, for example). This older version was chosen for ease of interpretation, however, more recently determined phase relations are used in modern research. You may use your mouse wheel and mouse to zoom and pan the diagram to see more detail. Press the "Recenter" button to return to the original view.