Which fault is characterized by a hanging wall moving upward relative to the footwall?

Which fault is characterized by a hanging wall moving upward relative to the footwall?

• A. Normal fault
• B. Reverse/thrust fault
• C. Strike-slip fault
• D. Transform fault

Answer: (B)

In a reverse or thrust fault, compression squeezes the rocks so the block above the fault plane (the hanging wall) is pushed up relative to the block below (the footwall). This upward movement of the hanging wall is the defining feature of these faults. It occurs at convergent plate boundaries where rocks are being compressed, often creating mountains. In contrast, a normal fault forms when the crust is pulled apart (extension); the hanging wall slides downward relative to the footwall. Strike-slip or transform faults involve mainly horizontal (lateral) movement along the fault with little vertical offset, so they don’t exhibit the hanging wall rising. So, the hanging wall moving upward relative to the footwall points to a reverse or thrust fault, produced by compression.

In a reverse or thrust fault, compression squeezes the rocks so the block above the fault plane (the hanging wall) is pushed up relative to the block below (the footwall). This upward movement of the hanging wall is the defining feature of these faults. It occurs at convergent plate boundaries where rocks are being compressed, often creating mountains.

In contrast, a normal fault forms when the crust is pulled apart (extension); the hanging wall slides downward relative to the footwall. Strike-slip or transform faults involve mainly horizontal (lateral) movement along the fault with little vertical offset, so they don’t exhibit the hanging wall rising.

So, the hanging wall moving upward relative to the footwall points to a reverse or thrust fault, produced by compression.