Which one of the following statements is not correct?

Question

Accepted Answer

The statement "The entire peninsular India is made of only Archaean Rocks" is not correct because while Archaean rocks form a significant portion of the Peninsular India's basement, the region also contains rocks from other geological periods and formations.

Here's why the other options are incorrect:

*   **Option 2: The Peninsular gneiss is known as Bengal gneiss.** This statement is incorrect because while gneiss is a common rock type in the Peninsular region, and Bengal Gneiss is a specific type of gneiss found in that region, the Peninsular gneiss is not *exclusively* known as Bengal gneiss. There are various types of gneiss found in the Peninsular region, each with its own characteristics and regional names.

*   **Option 3: The oldest rocks in India belong to the Archaean group.** This statement is generally considered correct. The Archaean rocks represent the earliest crustal formations and are the oldest rocks found in India.

*   **Option 4: The central part of Himalayas are made of Archaean rocks.** This statement is incorrect. The Himalayas are primarily composed of sedimentary and metamorphic rocks formed during the collision of the Indian and Eurasian plates. While some older rocks might be present in certain areas due to tectonic uplift and folding, the central part is not predominantly made of Archaean rocks. The Himalayas are much younger than the Archaean rocks.

Therefore, only Option 1 is definitively incorrect, making it the correct answer. The Peninsular India is geologically diverse and contains rocks from various periods, not just the Archaean.