Question

A northerly dipping fault (F-F) has displaced beds P, Q and R. The thickness of the beds across the fault is same. Identify the fault type(s). 

• A. Dextral fault
• B. Reverse fault
• C. Normal fault
• D. Sinistral fault

Hint:

Normal faults are common in regions experiencing extensional tectonic forces, where the crust is being pulled apart.

Answer 1

The Correct Option is B, D

Step 1: Identifying the fault type.
A normal fault occurs when the hanging wall moves downward relative to the footwall, often in response to extensional stress. The displacement of beds across a normal fault results in the stretching of the crust.

Step 2: Analyzing the options.
(A) Dextral fault: Dextral faults involve horizontal motion of the blocks, but not necessarily vertical displacement.
(B) Reverse fault: Reverse faults involve the hanging wall moving upwards, typically caused by compressional stress.
(C) Normal fault: Correct — A normal fault is consistent with the described displacement, where the hanging wall moves down.
(D) Sinistral fault: Sinistral faults are characterized by left-lateral motion, but they don't necessarily fit the description provided.

Step 3: Conclusion.
The correct answer is (C) Normal fault.