Uranium Transport in F-Cl-Bearing Fluids and Hydrothermal Upgrading of U-Cu Ores in IOCG Deposits

Figure 1

Contrasting U-Cu distribution in three samples from the Olympic Dam IOCG deposit, South Australia, illustrated by synchrotron-micro-XRF imaging of selected samples described in detail by Macmillan et al. [15]. Mineralogical and grade data are taken from Macmillan et al. [15]. The RGB maps show Cu (blue), U (green), and Fe (red) distribution (colour scale at the bottom right). In (a) (uraninite-dominated ore), Cu and U distribution mirror each other, suggesting coprecipitation of the two metals. Mineralogy is dominated by uraninite. In (b) and (c), the main U minerals are coffinite and brannerite, and U distribution is diffuse and overprints the ore textures, suggesting a secondary origin. The maps were collected at the XFM beamline, Australian Synchrotron. See Li et al. [40] for details of data collection and processing.

(a)

(b)

(c)