But suppose the dip direction is not shown on the fault. Now it's a little more complicated. If the fault is dipping, the dip direction can be determined by the "V" pattern where it crosses a canyon or stream valley. From studying tilted rocks, we know the trace of a tilted layer will make a "V" shape in the direction of its dip when crossing a stream valley. Likewise, the fault plane will form a "V" when crossing a stream valley. This "V" points in the direction of dip-- and the direction of dip indicates the hanging wall block.