Dynamic Permeability Related to Greisenization Reactions in Sn-W Ore Deposits: Quantitative Petrophysical and Experimental Evidence

Figure 12

(a) Vertical evolution of the permeability and whole-rock Sn, W, and Cu contents in drill hole SCB2. The spatial correlation between rock permeability and in metal contents suggests that greisen was probably a preferential pathway for fluids related to the main mineralization stages occurring in the Panasqueira vein system. Greisen pores infilled by ore-bearing minerals: (b) cassiterite (transmitted light), (b) chalcopyrite (reflected light), and (d-e) chalcopyrite and sphalerite (SEM-BSE images). Note the presence of sulfides within the cleavage planes of muscovite suggesting that these weakness planes may be potential pathways for fluids. Abbreviations from Whitney and Evans [45]: Ccp: chalcopyrite; Cst: cassiterite; Ms: muscovite; Py: pyrite; Qz: quartz; Sp: sphalerite.

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