In a reverse or thrust fault, the hanging wall moves in which direction due to compressional stress?

In a reverse or thrust fault, the hanging wall moves in which direction due to compressional stress?

• A. Up
• B. Down
• C. Left
• D. Right

Answer: (A)

Compression squeezes the crust, causing a reverse fault where the hanging wall is pushed up relative to the footwall. The hanging wall is the block above the fault plane, and with reverse motion the force drives it upward along the fault as the crust shortens and thickens. Thrust faults are simply low-angle reverse faults, so the hanging wall still moves up, just along a gentler incline. This is in contrast to normal faults formed by extension, where the hanging wall moves downward.

Compression squeezes the crust, causing a reverse fault where the hanging wall is pushed up relative to the footwall. The hanging wall is the block above the fault plane, and with reverse motion the force drives it upward along the fault as the crust shortens and thickens. Thrust faults are simply low-angle reverse faults, so the hanging wall still moves up, just along a gentler incline. This is in contrast to normal faults formed by extension, where the hanging wall moves downward.