I ran into a former work colleague who was much moreAu Fait with...

I ran into a former work colleague who was much more
Au Fait with oil exploration and seismic reflection
than I am.

I asked him the question "Would an oil company drill
for oil/gas based on gravity data without doing seismic?"
His answer was instantaneous and to the point "Not unless
they wanted to waste their money they wouldn't. They all
do 3D these days"

This guy has been retired for about ten years but his
answer was still scary. Do we have any oil exploration
or seismic reflection experts who read these posts?