GEOLOGY

Detailed explanation-1: -Metamorphic Microstructures. Poikiloblasts. Commonly a porphyroblast will grow by addition of material to its outer surface more rapidly than unwanted material (such as matrix quartz grains) can be removed from the interface. The porphyroblast traps the material as inclusions, forming a poikiloblast.

Detailed explanation-2: -poikiloblastic (comparative more poikiloblastic, superlative most poikiloblastic) (geology) Describing the texture of a metamorphic rock that has small idioblasts of one constituent lying within larger xenoblasts.

Detailed explanation-3: -Common metamorphic rocks include phyllite, schist, gneiss, quartzite and marble.

Detailed explanation-4: -Large amounts of granitic intrusions are also associated with regional metamorphic rocks. The most common regional metamorphic rocks are slates, schists and gneisses.

Detailed explanation-5: -Porphyroblastic: a crystalloblastic texture with minerals of two or more distinct grain sizes. The large crystals are called porphyroblasts. Poikiloblastic: a texture in which large porphyroblasts include numerous small mineral grains.