Richardhead what are you thinking??
For you fisherman out there that use a sounder for finding fish, if your sounder says there is fish there, THERE IS FISH THERE.
As an X fisher person you should know that when a sounder shows a fish you have no idea what the fish is until you sample it (catch it). Just like geophysis, just because you see an anomaly you have no idea what it is until you sample it (drill it). Also, a sounder can show debris in the water, reflections and artifacts as well just like geophysics. Things may not always be as they appear. Oh well... the X fisher does not even understand the equipment he used in his own profession and he wants you all to belove he is a geology expert. Good luck with that.