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Gurmeet Singh posted an Question
October 07, 2020 • 16:03 pm 30 points
  • IIT JAM
  • Geology (GG)

Sir topic is - assimilation i got the core meaning of assimilation but didn't get this paragraph. kindly help me

TOtal dissolution involving total disappearance of the solid phase. In general it is a complex process of reciprocal reaction between magma and invaded rock. During the process of reaction, due to ionic exchange between liquid and crystals, minerals are changed into those crystalline phases with which the liquid was already saturated. The end product is a contaminated igneous rock which was at no time entirely liquid and which is made up of materials contributed partly by the original rock and partly by the wall-rock. The rock formed in this way is naturally of hybrid origins, which are particularly common along the borders between intrusive and invaded rocks.

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    Rahul kumar

    By reciprocal reaction, they want to say that magma is crystallizing the high temperature minerals (like Forsterite) and at the same time incorporating low melting point minerals (like quartz, k feldspar) from the invaded rock into the magma. This process has lead to the shifting of magma composition towards felsic.

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    Rahul kumar Best Answer

    The paragraph is related to the magmatic differentiation process. Any melt coming to the surface interacts with the crustal rocks and incorporate the part of crustal rocks into them. As the successive differentiation occurs (result of reaction between melt and wall rocks) the composition of magma changes. By the time, the magma reaches to the surface the Earth, the composition of magma has changed very significantly than it's initial composition. All magma generated in mantle are of mafic to ultramafic in composition. As the magma comes to the surface, they interacts with crustal rocka and their composition shifted towards felsic. The interaction takes place as a result of reaction between the magma and rock forming minerals (silicates) in the Earth.

    eduncle-logo-app

    sir, in the 1st line, what he is talking about reciprocal..?

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    Sajan sarthak best-answer

    Assimilation is the process whereby solid or fluid foreign material is incorporated into magma. The term implies no specific mechanism and the process depends on many factors, including temperature, cooling rate of the magma, gas pressure, and the composition of the material being assimilated. The result is a contaminated magma and, on cooling, rocks that are referred to as being contaminated. Wholesale assimilation requires the magma to be superheated, which is rarely the case for a fractionating magma. Hybridization can be synonymous with contamination but most commonly it refers either to mixing of two magmas or to one magma digesting earlier-formed magmatic material. Reactions involved in the assimilation of sedimentary material by basic magma are given by Bowen (1928): magma crystallizing early-formed high-temperature members of the continuous and discontinuous reaction series incorporate the lower-temperature phases in the sedimentary material into the liquid fraction....

    eduncle-logo-app

    congratulations sir.

    eduncle-logo-app

    Thanks gurmeet

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