Which type of metamorphism is caused by high temperature and high pressure?
Metamorphism occurring at increasing pressure and temperature conditions is known as prograde metamorphism, while decreasing temperature and pressure characterize retrograde metamorphism. Metamorphic petrology is the study of metamorphism.
What causes the increased temperature and pressure in regional metamorphism?
The pressure and heat that drive metamorphism are consequences of three forces: (a) internal heat of the Earth. (b) weight of the overlying rock. (c) horizontal or tectonic forces that cause the rocks to deform.
What happens in metamorphism?
Metamorphism is a process that changes preexisting rocks into new forms because of increases in temperature, pressure, and chemically active fluids. Metamorphism may affect igneous, sedimentary, or other metamorphic rocks.
Why do rocks change during metamorphism?
Metamorphism occurs because some minerals are stable only under certain conditions of pressure and temperature. When pressure and temperature change, chemical reactions occur to cause the minerals in the rock to change to an assemblage that is stable at the new pressure and temperature conditions.
What type of metamorphism occurs at low temperatures and high pressures?
As metamorphic processes go, burial metamorphism takes place at relatively low temperatures (up to ~300 °C) and pressures (100s of m depth). To the unaided eye, metamorphic changes may not be apparent at all.
What happens to minerals as temperature and pressure increase?
What are the changes that occur in rocks during the process of metamorphism?
Metamorphism may affect igneous, sedimentary, or other metamorphic rocks. The changes brought about include the formation of new minerals, increase in grain size, and modification of rock structure or texture, all of which depend on the original rock’s composition and the intensity of the metamorphism.
What happen during metamorphism?
What is metamorphism and metamorphic rocks?
metamorphism, mineralogical and structural adjustments of solid rocks to physical and chemical conditions differing from those under which the rocks originally formed. Changes produced by surface conditions such as compaction are usually excluded.
What is meant by load metamorphism?
It is also called clastic metamorphism, mechanical metamorphism or dislocation metamorphism and is brought about by conditions in which pressure factor plays a dominant role. Sometimes the pressure is of the type of hydrostatic type such as load of the overlying rocks. The process is then called load metamorphism.
Why does the grade of metamorphism generally increase with depth?
The grade of metamorphism generally increases with depth for the simple reason that both temperature and pressure factors become strong and stronger at deeper levels within the crust of the earth. This fact has given birth to the concept of Metamorphic Zones that signify the range of metamorphic effects at different depths below the surface.
How do metamorphic processes change the composition of minerals?
These processes may induce changes varying from simple baking effect (optalic metamorphism) to complete or nearly complete recrystallisation of almost all of the original minerals.