Geo Question, page-9

... Don't worry about this terminology and don't try to interpret prospectivity based on if you aren't a geo.

In the old days..

The hanging wall is where a miner would "hang" his lamp

The foot wall is what he is standing on.

There are no generalised rules that can be applied to prospectivity above or below the "ore body".. it will be unique for each deposit and commodity type.