The blood pressure decreases and complaints, such as fatigue and lassitude, make themselves felt. These symptoms may also occur after the meal because the blood gathers in the area of the digestive organs and is missing in the brain. Dizziness.
Metamorphic rocks have been modified by heat, pressure and chemical processes, usually while buried deep below Earth's surface. Exposure to these extreme conditions has altered the mineralogy, texture and chemical composition of the rocks. There are two basic types of metamorphic rocks. Foliated metamorphic rocks such as gneiss, phyllite, schist, and slate have a layered or banded appearance that is produced by exposure to heat and directed pressure.
Rocks and the Rock Cycle. 1  Metamorphic Rocks-Metamorphic rocks are formed by great heat and pressure. 2  They are generally found inside the Earth's crust where there is enough heat and pressure to form the rocks. 3  Metamorphic rocks are often made from other types of rock. They are generally found inside the Earth's crust where there is enough heat and pressure to form the rocks. 2  Metamorphic rocks are often made from other types of rock. 3  For example, shale, a sedimentary rock, can be changed, or metamorphosed, into a metamorphic rock such as slate or gneiss.