Did you get the news?, page-43

Interpreting seismic data is something like an art, sometimes it hits you in the face its so obvious, and at other times is very vague if you don't have years of experience.

Unfortunately the economic viabilty (of spotting DHI's, and sometimes it can be very subjective), has nothing to do with the fact that it sometimes looks like what hangs between John Holmes legs, or whether its like trying to find a needle in a haystack.

But having found B Johnny Holmes, then at least you know that either gas or oil is present (but not able to tell what quantity).

The reason why they call them DHI's or bright spots is because they are 1) horizontal (when the surrounding rock relections are not), and 2) represent a dramatic change in accoustic velocity (basically a density interface), which allows a reflection in the noise generated by the seismic noise generator. Its sort of like a significant change in material (i.e air/water etc), except its represents whats beneath the surface. If you want to think of it another way try think of how a Radar systems works as you are cruising down the road at 130km/hr, it only works because a signal bounces of your car.

mmmmm'm not overly clear, so sorry about that, some will get others won't, and to others its like sucking eggs.