First or all, "oil" in the search doesn't giv meaningful results. Wiki et al say that oil is in "great abundance" under desert planets. I basically turned two desert planets into a Swiss cheese and found 2-3 shallow pools of oil in one location only. So not that abundant, I found a lot more water than oil.. Also a large Glitch castle and Apex science base, but I digress. Is the oil supposed to be near surface where you can get daylight by making holes in the background? I shouldn't actually dig in but only explore existing caverns? Its only in the sandy bits, not bones etc?