I'm very rusty on gas and oil drilling too hoppie but I'll give it a go.
I would say that the primary reason for switching to lighter mud is because they are getting closer to the potential pay zones. The mud engineer, (lol that's what I always wanted to be as a kid when we built dams in the local creek), needs to mud log by examining the mud cuttings for the presence of oil and gas under an ultraviolet light.
GDN Price at posting:
7.1¢ Sentiment: Buy Disclosure: Held
