Chorea is an abnormal involuntary movement disorder, one of a group of neurological disorders called dyskinesias. The term chorea is derived from the Ancient Greek: ÏÎ¿ÏÎµÎ¯Î±, as the quick movements of the feet or hands are comparable to dancing. The term hemichorea refers to chorea of one side of the body, such as chorea of one arm but not both.
Metamorphic rocks are most likely found at a site that is  deep under ground. Metamorphic rocks are formed by other materials  under great amounts of pressure. This pressureâ¦ is caused by plate  collisions in the lithosphere.
Pictures of Metamorphic Rocks. Metamorphic rocks are those that form by the effects of heat, pressure and shear upon igneous and sedimentary rocks. Some form during mountain-building by forces of regional metamorphism, others from the heat of igneous intrusions in contact metamorphism.A third category forms by the mechanical forces of fault movements: cataclasis and mylonitization. This is just a starting point to explore the variety in metamorphic rocks.etamorphic rocks are those that form by the effects of heat, pressure and shear upon igneous and sedimentary rocks.