This question came in the UPSC Civil Services Exam (Prelims) 2024 – General Studies Paper 1
1. Pyroclastic debris
2. Ash and dust
3. Nitrogen compounds
4. Sulphur compounds
How many of the above are products of volcanic eruptions?
(a) Only one
(b) Only two
(c) Only three
(d) All four
Answer: (d) All four
Topic: Physical Geography
Explanation: A volcano is a place where gases, ashes and/or molten rock material – lava – escape to the ground. A volcano is called an active volcano if the materials mentioned are being released or have been released out in the recent past. The layer below the solid crust is mantle. It has higher density than that of the crust. The mantle contains a weaker zone called asthenosphere.
It is from this that the molten rock materials find their way to the surface. The material in the upper mantle portion is called magma. Once it starts moving towards the crust or it reaches the surface, it is referred to as lava. The material that reaches the ground includes lava flows, pyroclastic debris, volcanic bombs, ash and dust and gases such as nitrogen compounds, sulphur compounds and minor amounts of chlorene, hydrogen and argon.
Source(s): NCERT Geography Class 11 Textbook: Chapter 3 Interior of the Earth
Difficulty level: Easy as straight forward from NCERT Textbook
Written By: Editor