gannatrade
It does not necessarily mean that blue (magnetic low) is the good stuff. However, I understand that the placement of blue at the extremities of anticlines definitely requires ground follow-up work.
Also, the way I see it, DSO Marra Mamba outcropping, or very near to the surface, will read as magnetic highs (pinks and reds). You may have notices that Jocelyn is wearing red lipstick.
