RAS question
Delhi Supergroup rocks are found in which part of Rajasthan?
Correct answer: (C) NE Aravalli (Alwar-Jaipur).
Delhi Supergroup rocks in Rajasthan are found in the north-eastern Aravalli belt, especially around the Alwar-Jaipur sector.
Explanation
In Rajasthan, the Delhi Supergroup is associated with the north-eastern Aravalli belt, especially the Alwar-Jaipur sector. Its rocks also occur in the Ajmer and Udaipur areas. The Jaipur district groundwater atlas records Delhi Supergroup rocks, including quartzite, schist, phyllite and marble, in the north-eastern part of Jaipur district. Across these areas, Delhi Supergroup formations include quartzite, arkose, conglomerate, limestone or marble, schist, slate and phyllite. Therefore, option C is correct: these rocks belong to the Aravalli geological belt, not to the southern plains, western desert or Hadoti plateau.
Why the other options are wrong
- (A) The southern plains are not the setting of the Delhi Supergroup in Rajasthan; the relevant setting is the metamorphic rocks of the north-eastern Aravalli belt.
- (B) The western desert is associated with younger rocks, not with the Delhi Supergroup belt of the Aravallis.
- (D) The Hadoti plateau belongs to a different geological province and is associated with Vindhyan rocks, not the Delhi Supergroup.
Concept
Rajasthan's major rock systems are distributed across the Aravalli belt, desert, plains and plateau regions. For RAS preparation, it is important to match rock systems with their correct locations because questions often connect physiography, minerals, groundwater and regional geology with map-based facts.