Question

Which of the following statements are correct?
I. In a planar tabular cross-bedding, the upper and lower bounding surfaces are planar and parallel
II. In a planar tabular cross-bedding, the upper and lower bounding surfaces are planar but not parallel
III. In a trough cross-bedding, both the upper and the lower bounding surfaces are curved
IV. In a trough cross-bedding, the upper bounding surface is planar and the lower bounding surface is curved

• A. II and III
• B. II, III and IV
• C. I, II and III
• D. I, II and IV

Hint:

Cross-bedding can be used to interpret the depositional environment, with planar and trough types being common in sedimentary rocks.

Answer 1

The Correct Option is D

Step 1: Understanding Cross-bedding Types.
- Planar tabular cross-bedding: Both the upper and lower surfaces are planar and parallel (I is true).
- Trough cross-bedding: The upper bounding surface is planar and the lower bounding surface is curved (IV is true).
- In planar tabular cross-bedding, the upper and lower surfaces can also be planar but not parallel, which happens in some cases (II is true).
- In trough cross-bedding, both surfaces are curved (III is true).
Step 2: Conclusion.
The correct answer is (B) II, III and IV, as these statements accurately describe the types of cross-bedding.