Skip to main content

What is magma? What is the importance of magma in geology world? What is the composition of it? What are the classification of it?

 ORIGIN AND GENERATION OF MAGMA



Before knowing about the origin and generation of magma, we need to be familiar with the term “Magma”. So, magma is extremely hot molten or semi-molten rocks, which are found beneath the earth's surface from which Igneous rocks are formed. When magma comes out of the surface of the earth, then the magma is called Lava. Basically, magmas are formed from pre-existing rocks like metamorphic or sedimentary rocks. As we know that, the temperature and pressure increase with depth. So, at a great depth below the earth's surface, the temperature and pressure cross 200 degrees Celsius and 350 MPA respectively, the pre-existing rocks start to melt, and then these pre-existing rocks converted into molten or semi-molten state and magma formed. The temperature of magma can be directly measured with the help of a “pyrometer or thermocouple”. But it is very difficult to measure the temperature of intrusive magma. The temperature of extrusion lavas is mostly in the range of 800 degrees Celsius to 1200 degrees Celsius.

CHEMICAL COMPOSITION OF MAGMA




The substance organization incorporates components, oxides, and the various kinds of minerals present in magma. By and large, magma is comprised of just eight components, arranged by significance: Oxygen, Silicon, aluminum, iron, calcium, sodium, magnesium, and potassium. Significant oxides are- silica (SiO2), aluminum oxide (Al2O3), iron oxide (FeO), magnesium oxide (MgO), carbon dioxide (CO2), sodium oxide (Na2O), carbon monoxide (CaO), nitrogen dioxide (N2o), and so on Some significant minerals are-Feldspar, Pyroxene, Quartz, mica, etc. 


CLASSIFICATION OF MAGMA

For the most part, magma is characterized into three kinds-

1) Basaltic magma: Basaltic magma is ordinarily delivered by direct liquefying of the Earth's mantle, the district of the Earth beneath the external outside. On mainlands, the mantle starts at profundities of 30 to 50 km. Safeguard volcanoes, like those that make up the Islands of Hawai'i, are made for the most part out of basalt. Here the measure of calcium, iron, and magnesium is high, yet the measure of sodium and potassium is low. Here the scope of temperature is going from 1000 degrees Celsius to 1200 degrees Celsius. The silica rate present in basaltic magma is between 45% to 55%. 


2) Andesitic magma: Granitic, or Rhyolitic, magmas, and andesitic magmas are created at joined plate limits where the maritime lithosphere (the external layer of Earth made out of the outside and upper mantle) is subducted so its edge is situated beneath the edge of the mainland plate or another maritime plate. Here the measure of Calcium, magnesium, iron, sodium, and potassium is moderate. Here the scope of temperature is going from 800 degrees Celsius to 1000 degrees Celsius. The silica rate present in andesitic magma is between 55% to 65%. 


3) Rhyolitic magma: Rhyolitic magma structures because of the wet softening of mainland covering. Rhyolites are rocks that contain water and minerals that contain water, like biotite. ... This crystallization delivers the basaltic magma's warmth, making the temperature of the mainland outside ascent and liquefy. Rhyolites typically structure in mainland or landmass edge volcanic ejections where granitic magma arrives at the surface. Rhyolites are seldom created at maritime ejections. Here the measure of calcium, magnesium, and iron are low, yet the measure of sodium and potassium is high. Here the scope of temperature is going from 600 degrees Celsius to 800 degrees Celsius. The silica rate present in Rhyolites magma is between 65% to 75%.

Comments

Popular posts from this blog

What is a volcano and how a volcano is formed?

                                             Answer:  A volcano is a dome or conical-like structure, which is formed due to volcanic eruption at the divergent plate boundary.             In simple words, volcanoes are formed due to volcanic eruptions.           Due to the decay of radioactive substances beneath the surface of the earth or in the earth’s mantle, a large amount of heat produced below the earth's surface, which melts the rocks slowly and forms a thick flowing layer of substance is called magma (consisting of the mixer of minerals, water vapor, different kinds of dissolved gases like carbon dioxide, sulfur, carbon monoxide, etc. Magma continuously exerts pressure on the earth's surface to escape from the earth's mantle. As a result, the surface of the earth becomes we...

What is metamorphic zone and its types? What is Metamorphic facies? What is grades of metamorphism? What are the texture of metamorphic rocks?

  Metamorphic Zone and Metamorphic facies: Metamorphic zone is an area where the same combination of minerals occurs in the bedrock during the metamorphism process. Metamorphic zones occur because metamorphic minerals have a unique range or interval of temperature and pressure at which they are stable. There are three types of metamorphic zones- 1)       Epizone: This zone of metamorphism occurs near the earth’s surface. In this zone, generally Cataclastic metamorphism conditions are observed. 2)       Mesozone: It is the intermediate zone of metamorphism, which is found below the Epizone. The mesozone condition that is the temperature and pressure promotes the regional metamorphism. 3)       Katazone: The bottommost metamorphic zones are known as Katazone. In this zone, the plutonic metamorphism is taken place.   Grades of metamorphism: The degree or intensity of metamorphism that has affecte...

What is Fault? How they are formed? What are the classifications of fault? Terminology of a Fault

  A fault may be defined as a well-defined crack along which the rock masses on either side have relative displacement. The displacement along a fault may be less than a meter, several meters, or many kilometers. Faults results from tensional as well as compressional forces TERMINOLOGY OF A FAULT Fault Plane : The fracture surface of a fault, along which relative movement has taken place, is called a “fault plane”. A fault plane is generally inclined but in some other cases, the fault plane may be markedly curved or undulating.    In a fault, there may be a number of parallel shear fractures along which the fault movement is distributed. Such a fracture zone is called a “shear Zone”. Hanging Wall and Foot Wall:  The block of rock lying above the fault plane such block of rock is called a hanging wall and if it is lying below the fault plane, then it is known as a footwall. Vertical faults have neither hanging wall nor footwall. Fault Scarp:  A fault scarp is a c...