Formation of Oil shale and Porphyry

Oil shale

Porphyry

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1 Formation

1.1 Formation

Oil Shale forms on the beds of seas and lakes and its formation starts with the organic debris settling and accumulating at the bottom of a lake or sea which are then transformed into rock with the help of high temperature and pressure.

Porphyry is formed in two stages: the magma cools slowly deep within the crust or the magma is cools rapidly as it erupts from a volcano, creating small grains that are usually invisible to naked eye.

1.2 Composition

1.2.1 Mineral Content

Albite, Biotite, Calcite, Chert, Chlorite, Dolomite, Hematite, Micas, Muscovite or Illite, Pyrite, Quartz, Silica, Sulfides

Biotite, Chert, Feldspar, Garnet, Graphite, Quartz, Silica

1.2.2 Compound Content

Ca, Fe, Mg, Silicon Dioxide, Sodium

Aluminium Oxide, CaO, Iron(III) Oxide, Potassium Oxide, MgO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide

1.3 Transformation

1.3.1 Metamorphism

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1.3.2 Types of Metamorphism

Not Applicable

Burial Metamorphism, Cataclastic Metamorphism, Contact Metamorphism, Hydrothermal Metamorphism, Impact Metamorphism, Regional Metamorphism

1.3.3 Weathering

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1.3.4 Types of Weathering

Biological Weathering, Chemical Weathering, Mechanical Weathering

Biological Weathering, Chemical Weathering, Not Registered

1.3.5 Erosion

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1.3.6 Types of Erosion

Chemical Erosion, Sea Erosion, Water Erosion

Chemical Erosion, Coastal Erosion, Glacier Erosion

Oil shale and Porphyry Formation

Formation of rocks is a long process and hence, Oil shale and Porphyry formation sounds very interesting. According to the formation, all rocks are divided into :Igneous Rocks, Fossil Rocks and Metamorphic Rocks. Igneous rocks form by crystallization of magma or lava. The magma is made up of various components of pre-existing rocks which have been subjected to melting either at subduction zones or within the Earth's mantle. Igneous rocks are generally seen at mid ocean ridges or in intra-plate hotspots. Sedimentary rocks are formed when sediments accumulate gradually. As the sediments are buried they get compacted as more and more material is deposited on top. Eventually the sediments become so dense that they form a rock. Metamorphic rocks are rocks which once existed as igneous or sedimentary rocks but have been subjected to varying degrees of pressure and heat within the Earth's crust. Get to know all about formation of Oil shale and Porphyry, composition of Oil shale and Porphyry and their transformation.