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Geology/calc-alkaline vs alkaline igneous rocks


QUESTION: define the following with example.and what is ophiolite and it stratigraphy
1: calc-alkaline rock
2: alkaline rock


ANSWER: Calc-alkaline and alkaline division is based on the ratio of alkali element contents (K2O and Na2O) to Silica (SiO2). Those which have high alkali elements at a specific silica content are called alkaline. This is a division for igneous rocks.

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QUESTION: thanks but sir
in which environment thy found ? and how they form ?

Ophiolites are basaltic igneous rocks which are originally formed in mid-ocean ridges and are subsequently replaced on the continents when an oceanic plate collides with a continental one.
Alkaline rocks are often formed at rifts (openings in the plates which lead to formation of new plate boundaries).
Calc-alkaline rocks is island arcs or magmatic arcs where another plate, say an oceanic plate, is subducting beneath another plate.
Calc-alkaline rocks show subduction processes and alkaline rocks show rifting processes.


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Meisam Rasouli Beirami


Magmatic Ore deposits; Igneous Rocks; Uranium Ore Deposits; Mississippi Valley Type (MVT) Deposits; Remote Sensing; Satellite Imagery Processing;


I have done a thesis on magmatic uranium deposits. I ma currently working on MVT ore deposits and their exploration via satellite imagery.

Shiraz University, Shiraz, Iran Golestan University, Gorgan, Iran

Bachelor's degree of geology: Tehran university, Iran. MSc of economic geology: Gorgan university, Iran. PhD student of economic geology: Shiraz university, Iran.

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