RE:RE:RE:RE:RE:Relaxed Sporty, The people fudding around should read up on the nuclear magnetic resonance spectroscopy logging tool and then try to suggest that they don't know what the formation fluid type is. Together with density, gamma, neutron, spontaneous potential, resistivity logs correlated with litholigy from the mud loggers and seismic they already pretty much know what's there. Lol, I just read up on all of this stuff after googling it. Now I'm an expert. NOT! But it is fascinating learning about it.
https://en.m.wikipedia.org/wiki/Well_logging