Question map
Consider the following statements about rock structure: 1. Conglomerates are clastic sedimentary rocks. 2. Slate is a non-clastic sedimentary rock. 3. Granite is a plutonic igneous rock. 4. Basalt is an extrusive igneous rock. Which of the statements given above are correct?
Explanation
Statement 1 is correct as conglomerates are mechanically formed (clastic) sedimentary rocks composed of coarse-grained fragments like pebbles [3][4]. Statement 2 is incorrect because slate is a metamorphic rock formed from the transformation of clay or shale under heat and pressure, not a sedimentary rock [1][4]. Statement 3 is correct; granite is a plutonic (intrusive) igneous rock that solidifies slowly beneath the Earth's surface [2]. Statement 4 is correct as basalt is a common extrusive (volcanic) igneous rock that forms from lava cooling rapidly on the surface [3]. Therefore, statements 1, 3, and 4 are accurate descriptions of rock structures and classifications. Clastic rocks are specifically defined by the accumulation of fragments from pre-existing rocks, while plutonic and extrusive terms describe the cooling environment of igneous bodies.
Sources
- [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 13: Types of Rocks & Rock Cycle > 13.2. Sedimentary Rocks or Detrital Rocks > p. 171
- [4] Certificate Physical and Human Geography , GC Leong (Oxford University press 3rd ed.) > Chapter 2: The Earth's Crust > METAMORPHIC ROCKS > p. 19
- [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 13: Types of Rocks & Rock Cycle > Some Examples of Metamorphosis > p. 174
- [2] Geography of India ,Majid Husain, (McGrawHill 9th ed.) > Chapter 6: Soils > Parent Material > p. 1