What are characteristics of metamorphic rocks?
Metamorphic rocks were once igneous or sedimentary rocks, but have been changed (metamorphosed) as a result of intense heat and/or pressure within the Earth’s crust. They are crystalline and often have a “squashed” (foliated or banded) texture.
What are the subcategories of metamorphic rock?
Common metamorphic rocks include phyllite, schist, gneiss, quartzite and marble. Foliated Metamorphic Rocks: Some kinds of metamorphic rocks — granite gneiss and biotite schist are two examples — are strongly banded or foliated.
What are the three subcategories of metamorphic rocks?
The three types of metamorphism are Contact, Regional, and Dynamic metamorphism. Contact Metamorphism occurs when magma comes in contact with an already existing body of rock. When this happens the existing rocks temperature rises and also becomes infiltrated with fluid from the magma.
What is metamorphic Paragenesis?
Paragenesis is a petrologic concept meaning an equilibrium sequence of mineral phases. It is used in studies of igneous and metamorphic rock genesis and importantly in studies of the hydrothermal deposition of ore minerals and the rock alteration (vein metasomatism) associated with ore mineral deposits.
What are the 2 main classifications of metamorphic rocks?
There are two main types of metamorphic rocks: those that are foliated because they have formed in an environment with either directed pressure or shear stress, and those that are not foliated because they have formed in an environment without directed pressure or relatively near the surface with very little pressure …
What are 2 types of metamorphism?
There are two main types of metamorphism:
- Contact metamorphism—occurs when magma contacts a rock, changing it by extreme heat (Figure 4.14).
- Regional metamorphism—occurs when great masses of rock change over a wide area due to pressure exerted on rocks at plate boundaries.
How do you name a metamorphic rock?
By convention, when naming a metamorphic rock the mineral in the lowest quantity (garnet, in this case) is mentioned first. Notice that the muscovite micas define a very wavy foliation in the rock; this textural pattern of wavy micas is called a schistose foliation (Figure 11.5B).
What type of rock is shale?
Shale rocks are those that are made of clay-sized particles and are have a laminated appearance. They are a type of sedimentary rock. Shale is the abundant rock found on Earth. They are usually found in areas where gentle waters have deposited sediments that become compacted together.
What is ore Paragenesis?
Paragenesis, the sequence in which the minerals are formed in an ore deposit. Variations in the pressure and temperature and in the chemical constituents of a hydrothermal solution will result in the precipitation of various minerals at different times within the same ore deposit.
What is ACF diagram?
ACF diagram A three-component, triangular graph used to show how metamorphic mineral assemblages vary as a function of rock composition within one metamorphic facies. The minerals quartz and albite are assumed to be present in the rocks and are not shown on the diagram.
What type of rock forms from regional metamorphism?
Eclogite (“ECK-lo-jite”) is an extreme metamorphic rock formed by regional metamorphism of basalt under very high pressures and temperatures. This type of metamorphic rock is the name of highest-grade metamorphic facies.
How is Paragenesis used in igneous rock formation?
Paragenesis is a petrologic concept meaning an equilibrium sequence of mineral phases. It is used in studies of igneous and metamorphic rock genesis and importantly in studies of the hydrothermal deposition of ore minerals and the rock alteration (vein metasomatism) associated with ore mineral deposits.
How is Paragenesis used in petrologic studies?
Jump to navigation Jump to search. Paragenesis is a petrologic concept meaning an equilibrium sequence of mineral phases. It is used in studies of igneous and metamorphic rock genesis and importantly in studies of the hydrothermal deposition of ore minerals and the rock alteration (vein metasomatism) associated with ore mineral deposits.
How is a metamorphic rock changed from its original form?
A metamorphic rock is one whose character has been changed from its original form by processes operating within the earth. They may be derived from pre-existing rocks (igneous , sedimentary and even metamorphic). A metamorphosed rock can be remetamorphosed through a process known as poly-metamorphism.
