This figure is used to pictorially represent the Importance of Understanding Ore Systems as a whole. It is a diagram showing how they are developed though the circulation of hot, metal-bearing fluids through the earth’s crust. This fluid migration and collection within a trap zone where the metals are deposited leaves a distinctive halo of altered rock many times the size of the deposit. By recognizing and understanding the various features — unique size, morphology, composition and internal zonation — of these halos, industry is better equipped to evaluate the commercial potential of the hidden deposits.
This figure is taken from Gold Deposits in Metamorphic Belts: Overview of Current Understanding, Outstanding Problems, Future Research, and Exploration Significance by David I. Groves Economic Geology; January 2003; v. 98; no. 1; p. 1-29; DOI: 10.2113/gsecongeo.98.1.1 and was used to represent gold deposit types that formed during early volcanism and sedimentation inconvergent margin settings, or were accreted to cratons in oceanic arcs, including epithermal Ag-Au, porphyry Cu-Au, and Au-rich volcanic-hosted massive sulfide deposits.