GENERAL GEOLOGY

Detailed explanation-1: -The outcome of prolonged dynamic metamorphism under these conditions is a rock called mylonite, in which crystals have been stretched into thin ribbons (Figure 10.34, right). Figure 10.33 Fault breccia, created when shear stress along a fault breaks up rocks.

Detailed explanation-2: -Cataclastic metamorphism is generally localized along fault planes (areas of detachment where rocks slide past one another). Cataclastic Metamorphism produces sheared, highly deformed rocks called mylonites.

Detailed explanation-3: -Metamorphic rocks The mylonites can be formed by converting many kinds of rocks, particularly those predominantly composed of quartz, feldspar, calcite, dolomite, sericite, and chlorite. The likely parent rocks are sandstone, granite, granodiorite, diorite, limestone, marble, and dolostone (Fig. 7.7).

Detailed explanation-4: -Unlike other kinds of metamorphism, metamorphic temperatures may not exceed 100-200 oC. Products of dynamic metamorphism, called cataclastic rocks, include ground-up and deformed rocks such as those seen in the fault zone above the knapsack in Figure 9.21.

Detailed explanation-5: -Mylonites generally develop in ductile shear zones where high rates of strain are focused. They are the deep crustal counterparts to cataclastic brittle faults that create fault breccias.