Consider the following statements : I. > Most magmas are a combination of liquid, solid and gas. II. > Water vapour and carbon dioxide are the principal gases dissolved in a magma. III. > Basaltic magma is hotter than the silicic magma. IV. > The magma so

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Q: 55 (IAS/2001)
Consider the following statements :
I. Most magmas are a combination of liquid, solid and gas.
II. Water vapour and carbon dioxide are the principal gases dissolved in a magma.
III. Basaltic magma is hotter than the silicic magma.
IV. The magma solidified between sedimentary rocks in a horizontal position is known as dike.
Which of these statements are correct ?

question_subject: 

Geography

question_exam: 

IAS

stats: 

0,82,68,82,14,22,32

keywords: 

{'basaltic magma': [0, 0, 1, 0], 'silicic magma': [0, 0, 1, 0], 'magma': [2, 0, 1, 1], 'most magmas': [0, 0, 1, 0], 'sedimentary rocks': [1, 0, 3, 1], 'principal gases': [0, 0, 1, 0], 'water vapour': [0, 0, 1, 2], 'dike': [0, 0, 1, 0], 'iv': [6, 110, 77, 8], 'carbon dioxide': [2, 0, 5, 6], 'gas': [9, 1, 9, 27]}

The correct answer is Option 1 - I, II, and III.

Statement I is correct because magma typically contains three components - a liquid portion (melt), a solid portion (minerals or crystals), and a gaseous portion (volatiles).

Statement II is accurate as water vapor and carbon dioxide are the main gases absorbed in magma. These gases often escape or "degas" as the magma ascends to the Earth`s surface.

Statement III correctly indicates that basaltic magma, composed mainly of basic silicates with relatively small amounts of silica, is hotter than silicic or felsic magma, which contains a large quantity of silica.

Statement IV is not accurate as a magma solidified between sedimentary rocks in a horizontal position is known as a sill, while a dike is a type of intrusion that occurs when magma cuts across established rock layers. Thus, it`s not included in the correct answer.

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