Which one of the following is a type of igneous rock ?
- A.Marble
- B.Halite
- C.Granite
- D.Shale
Correct answer
Explanation
The correct answer is C, Granite. Granite is an igneous rock, formed when molten magma cools and hardens. Because it cools slowly deep inside the earth's crust, its crystals grow large enough to be seen by the naked eye, so it is called an intrusive or plutonic igneous rock. It is made mainly of quartz and feldspar with some mica, is light in colour and very hard, and is widely used for buildings, floors and monuments. Basalt is the matching example of an extrusive igneous rock, which cools quickly at the surface after a volcanic eruption and so has fine grains; the Deccan Traps are made of it. Igneous rocks are called primary rocks because the others are formed from them. Option A is wrong because marble is a metamorphic rock, formed when limestone is changed by heat and pressure. Option B is wrong because halite, or rock salt, is a chemically formed sedimentary rock left behind when salty water evaporates. Option D is wrong because shale is a sedimentary rock made of compacted clay and silt. Exam tip: granite and basalt are igneous; limestone and shale are sedimentary; marble and slate are metamorphic.
Practice Questions
View allChemical weathering of rocks is much greater in a place with
- A.cold and dry climate
- B.hot and humid climate
- C.hot and dry climate
- D.cold and humid climate
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Chemical weathering is the breakdown of rocks through reactions such as solution, oxidation, carbonation and hydration, and all of these need water.
Read the full explanation →Which one of the following ocean currents is a cold current?
- A.South Atlantic Drift
- B.Mozambique Current
- C.East Australian Current
- D.Caribbean Current
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The South Atlantic Drift is part of the West Wind Drift, the cold eastward flow that circles Antarctica in the belt of the westerlies, around 40° to 50° south.
Read the full explanation →Which one of the following is the narrow belt parallel to the Shiwalik foothills where streams and rivers coming from the mountains deposit heavy materials of rocks and boulders ?
- A.Tarai
- B.Bhangar
- C.Bhabar
- D.Khadar
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As rivers come down from the mountains onto the plains, their slope suddenly drops and they can no longer carry their heaviest load.
Read the full explanation →Which of the following statements regarding earthquakes is/are correct ? 1. The point on the Earth's surface directly above the focus is called the epicentre of the earthquake. 2. Earthquakes generate Primary and Secondary waves that radiate outward from the earthquake focus. 3. Deep-focus earthquakes are likely to cause more damage than shallow-focus earthquakes. Select the answer using the code given below :
- A.1 only
- B.1 and 2 only
- C.2 and 3 only
- D.1, 2 and 3
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The focus, or hypocentre, is the point inside the Earth where the rocks first break and energy is released. The point on the surface directly above it is the epicentre, which is usually where shaking is felt first and strongest, so statement 1 is correct.
Read the full explanation →As per the India State of Forest Report 2021, which one of the following Himalayan states has the highest percentage of its geographical area under forest?
- A.Arunachal Pradesh
- B.Himachal Pradesh
- C.Sikkim
- D.Uttarakhand
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The India State of Forest Report 2021, published by the Forest Survey of India, Dehradun, put the forest cover of Arunachal Pradesh at about 79 per cent of its geographical area, the highest among the four Himalayan states listed.
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