gs1
150 Words10 Marks
Q.Describe the characteristics and types of primary rocks.
UPSC Mains 2022•Geography
Model Answer
Introduction
Primary rocks, commonly known as igneous rocks, are formed directly from the cooling and solidification of molten magma or lava. They represent the foundational rock type from which other rocks are derived, and their characteristics depend heavily on the composition of the molten material and the environment in which they cool.
Body
Characteristics of Primary Rocks
- Identification: They are identified by their distinct texture, density, color, and mineral composition. Their texture is determined by the shape, size, cooling duration, and crystalline arrangement within the rock.
- Absence of Fossils: Due to the intense heat of molten magma/lava during formation, fossils are not preserved in these rocks.
- Chemical and Physical Properties: They generally do not react with acids and tend to have a fine-grained, smooth texture.
- Hardness: They are typically hard and compact, making water percolation highly difficult.
Types of Igneous Rocks
- Intrusive Igneous Rocks: Formed when magma cools slowly deep beneath the Earth's surface, allowing large crystals to develop. Examples include granite and dolerite.
- Extrusive Igneous Rocks: Formed when lava reaches the Earth's surface and cools rapidly, resulting in fine-grained textures. Also known as volcanic rocks, examples include basalt and gabbro.
Conclusion
In conclusion, primary rocks serve as the fundamental building blocks of the Earth's crust, offering invaluable insights into the planet's geological evolution and internal processes.
Previous QuestionYou hold a responsible position in a ministry in the government, One day in the morning you received a call from the school of your 11-year-old son that you are required to come and meet the Principal. You proceed to the school and find your son in the Principal's office. The Principal informs you that your son had been found wandering aimlessly in the grounds during the time classes were in progress. The class teacher further informs you that your son has lately become a loner and did not respond to questions in the class, he had also been unable to perform well in the football trials held recently. You bring your son back from the school and in the evening, you along with your wife try to find out the reasons for your son's changed behaviour. After repeated cajoling, your son shares that some children had been making fun of him in the class as well as in the WhatsApp group of the students by calling him stunted, duh and a frog. He tells you the names of a few children who are the main culprits but pleads with you to let the matter rest. After a few days, during a sporting event, where you and your wife have gone to watch your son play, one of your colleague's son shows you a video in which students have caricatured your son. Further, he also points out to the perpetrators who were sitting in the stands. You purposefully walk past them with your son and go home. Next day, you find on social media, a video denigrating you, your son and even your wife, stating that you engaged in physical bullying of children on the sports field. The video became viral on social media. Your friends and colleagues began calling you to find out the details. One of your juniors advised you to make a counter video giving the background and explaining that nothing had happened on the field. You, in turn posted a video which you have captured during the sporting event, identifying the likely perpetrators who were responsible for your son's predicament. You have captured during the sporting event, identifying the likely perpetrators who were responsible for your son's predicament. You have also narrated what has actually happened in the field and made attempts to bring out the adverse effects of the misuse of social media.
A. Based on the above case study, discuss the ethical issues involved in the use of social media.
B. Discuss the pros and cons of using social media by you to put across the facts to counter the fake propaganda against your family.
Next QuestionHow will you explain that medieval Indian temple sculptures represent the social life of those days? (Answer in 150 words) (2022)