Question

On which of the following bases is the Dharwar succession of Karnataka divided into Lower and Upper Dharwar?
A. Unconformity,
B. Fossil evidence,
C. Geochronological data,
D. Economic minerals. Choose the correct answer from the options given below:

• A. A and B only
• B. B and C only
• C. C and D only
• D. A and C only

Hint:

Lower and Upper Dharwar divisions are mainly based on unconformity and geochronological data.

Answer 1

The Correct Option is D

Concept:
The Dharwar succession of Karnataka belongs to the Precambrian rocks. Its division is mainly based on geological relationships and age data.

Step 1: Check unconformity.
Unconformity is an important geological break between rock successions and helps divide older and younger units. \[ A \text{ is correct} \]

Step 2: Check fossil evidence.
Dharwar rocks are Precambrian, so fossil evidence is not the main basis for division. \[ B \text{ is incorrect} \]

Step 3: Check geochronological data.
Geochronological data gives numerical age information and helps distinguish Lower and Upper Dharwar successions. \[ C \text{ is correct} \]

Step 4: Check economic minerals.
Economic minerals may occur in these rocks, but they are not the main formal basis for dividing the succession. \[ D \text{ is incorrect} \] Therefore, the correct statements are: \[ A,C \] \[ \therefore \text{Correct Answer is (D)} \]