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.
The way that they form. Non-foliated metamorphic rocks form at low pressures but high temperatures, while foliated metamorphic rocks form at high pressures. Most non-foliated metamorphic rocks are generally formed by contact metamorphism and are termed âHornfelsâ. There are a few metamorphic rocks that form under pressure with little obvious foliation, such as marble or quartzite, however these are generally mono-mineralic rocks.