Monary Systems

By comparing the compositions of minerals and rocks with the compositions obtained from experimental work it becomes possible to estimate the PT conditions that control the igneous processes. The estimation of the phase relations of magmas and the magmatic sources, like the mantle and the subducted oceanic crust, therefore, form the basis for an understanding of the generation of igneous rocks. After the PT conditions have been estimated the next step is an analysis of the dynamic processes that control the temperature and pressure conditions. Such an analysis will involve the calculation of the temperature distribution in mantle plumes and ascending convection currents, an estimation of the velocity of dyke propagation, and calculations of the cooling rates of intrusions.