ENDOGENIC PROCESSES: PLUTONISM AND VOLCANISM

• Magma


  • Formed under certain circumstances in special location deep in the crust or in the upper mantle
  • Forms from partial melting of mantle rocks
• Partial melting of rocks


  1. Rocks are not pure materials

  2. As temperature rises, some minerals melt and others remain solid

  3. If same conditions maintained, same mixture of solid and melted rock is maintained
• Pressure increases with depth


  Higher pressure leads to higher melting points
• Decompression melting


  • Takes place when a body of rock is held at approximately the same temperature but the pressure is reduced
  • Happens because the rock is being moved toward the surface, either at a mantle plume or in the upwelling part of a mantle convection cell
• Flux melting


  Happens if a rock is close to its melting point and some water or carbon dioxide is added to the rock, the melting temperature is reduced and partial melting starts
• As magma moves toward the surface


  It interacts with the surrounding rock, typically leading to partial melting of the surrounding rock
• At very high temperatures (over 1300°C), most magmas are entirely liquid because there is too much energy for the atoms to bond together
• As temperature drops


  • Silicon and oxygen combine to form silica tetrahedra, and then the tetrahedra start to link together to make chains (polymerize)
  • This makes the magma more viscous (less runny)
• Intrusion


  • Magma that moves up into a volcano without erupting
  • Causes the volcano to grow on the inside
• Plutonism


  • All sorts of igneous geological activities taking place below the Earth's surface
  • In cases where magma infiltrates the Earth's crust but fails to make it to the surface, the process of magma differentiation gives birth to ideal conditions for metallogenesis
• Plutonites


  Igneous rock formations created when the process of crystallization and solidification of magma takes places below the Earth's surface and particularly in the crust
• Extrusion


  • Eruption of magmatic materials that causes land formation on the surface of the Earth
  • Magma extrusion causes the formation of volcanoes when the gas pressure is strong enough and there are cracks in the earth's crust
• Lava


  Magma that came out to the surface of the earth
• Magma can move up


  Because of a high pressure exerted by magma and gases
• Magma chamber


  The depth of the magma chamber causes the differences in the strength of volcanic eruptions
• Volcanism


  • All geological phenomena that occurs on the natural terrestrial surface, such as the creation of volcanoes and hot springs
  • Refers to all sorts of geological activities correlated with the flow and transportation of igneous material from the planet's interior towards the natural terrestrial surface
• Creation of volcanoes


  1. Energy generated by inductive currents flowing from the Earth's core towards the surface hits the upper layers in the form of pressure and smashes the overlaying rock formations

  2. Presence of dilated water vapor plays an important role in the creation of craters by assisting the flow of magma towards the surface
• Massive amounts of water vapor concentration in magmatic gases with an average value of 80% are emitted into the atmosphere during volcanic eruptions
• Volcanites


  • Molten material in the form of lava that undergoes the process of crystallization on the natural terrestrial surface
  • One of the major categories of igneous rock formations
  • Composed of gray, dull pink colored track basaltic lava with large phenocrysts and pyroclastic