The Difference Between a Normal and Reverse Fault
First you need to know a couple of other terms. These
terms come to us from the mining industry. When minors
were working a mine, they noticed that the ore tended to
occur along faults. When working at a fault, they would
hang their lanterns from the block of rock that was above
the fault. So, they called this the hanging wall block (see
attached drawing). Mean while, he would be standing on
the block that was below the fault. Thus it was called the
footwall block.
Imagine you are walking into the fault. Where would you
stand and where would you hang your lantern?
In a normal fault, the hanging wall block moves
downward with respect to the footwall block. In a reverse
fault the hanging wall block moves up with respect to the
footwall block.