Metamorphic Rocks geology
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Metamorphic rocks form from existing igneous, sedimentary, or other metamorphic rocks when they are subjected to high heat, pressure, fluids, or a combination of these deep within the earth or at tectonic plate boundaries. The process of metamorphism transforms rocks into more compact and denser varieties with new minerals formed through rearrangement or chemical reactions. Metamorphic rocks make up a large portion of the earth's crust and studying them provides insight into deep temperatures and pressures within the earth.
Metamorphic Rocks geology
- 1. What are Metamorphic Rocks ? Metamorphic rocks started out as some other type of rock , but have been substantially changed from their original igneous , sedimentary, or earlier metamorphic form.
- 2. Metamorphic rocks form when rocks are subjected to high heat , high pressure , hot mineral - rich fluids, or more commonly , some combination of these factors. Conditions like these are found deep within the earth or where tectonic plates meet . Process of Metamorphism : The process of metamorphism does not melt the rocks , but instead transforms them into denser , more compact rock . New minerals are created either by rearrangement of mineral component or by
- 3. reactions with fluids that enter the rocks . Pressure or temperature can even change previously metamorphosed rocks into new types . Metamorphic rocks are often squished , smeared out , and folded. Despite these uncomfortable conditions , metamorphic rocks do not get hot enough to melt,or they would become igneous rocks!
- 5. Metamorphic rocks make up a large part of the earth's crust and form 12% of the earth's land surface. They are classified by their protolieth, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the earth's surface , where they are subject to high temperature and the great pressure of the rock layers above . They can also form from tectonic processes such as continental collisions , which cause horizontal pressure , friction , and distortion. Metamorphic rock can be formed locally when rock called magma from the earth's interior .
- 6. The study of metamorphic rocks ( now i'urmafion of .llclaniorplm* Itork exposed at the earth's surface following erosion and uplift ) provide information about the temperatures and pressures that occur at great depths within the earth's crust . Origin Metamorphic rocks form one of the three great division of rock types . They are distinguished from igneous rocks , which
- 7. form from molten magma , and sedimentary rocks , which form from sediments eroded from exiting rock or precipitated chemically from bodies of water . Metamorphic rocks are formed when existing rock is transformed physically or chemically at elevated temperature , without actually melting to any great degree . The importance of heating in the formation of metamorphic rock was first noted by the pioneering Scottish naturalist , James Hutton, who is often described as the father of modern geology .
- 8. Why we study metamorphic rock? • Studies of metamorphic rocks provide insights into the physical and chemical changes that take place deep within Earth . • Knowledge of metamorphic processes and rocks is valuable , because metamorphic minerals and rocks have economic value . For example , slate and marble are building materials . • Metamorphic rocks are some of the oldest on earth , are widely exposed in the core areas , known as “ Shields “ of continents .
- 9. mtrud«j magma Dodv Agents of metamorphism These are three main sources of chemically active fluids : 1- Pore waters of sedimentary rocks 2- Fluids from cooling magma 3- Water from dehydration of water - bearing minerals like gypsum .
- 10. Recourses • An introduction to igneous and metamorphic petrology • The tectonic evolution of the Himalaya and Tibt.