Structural and litho-tectonic controls on Neoproterozoic base metal sulfide and gold mineralization in North Hamisana shear zone, South Eastern Desert, Egypt: The integrated field, structural, Landsat 7 ETM + and ASTER data approach

• Microscopic study in quartzites suggest presence of two phases of sulfide minerals.
• Early mineralization phase includes pyrite-pyrrhotite-argentite and invisible gold.
• Late phase includes pyrite-galena-sphalerite-chalcopyrite-covellite ± invisible gold.
• Merging image transformation of ETM +/ASTER provide detailed mapping of NHSZ area.
• Base-metal sulfide and associated gold are controlled by D3 deformational event.

The Hamisana shear zone (HSZ), is an excellent example of high strain shear belt of the Neoproterozoic Arabian–Nubian Shield (ANS), situated in a position between three major Pan-African terranes (SE Desert, Gabgaba, and Gebeit terranes). The north Hamisana shear zone area (NHSZ), cuts across sequences of island arc-related metasediment-metavolcanic, which are structurally overlain by ophiolitic nappes and intruded by a number of granitoids and gabbroic rocks. Although it is interesting geological-tectonic setting for base metal sulfide and gold ores, there is a lack of detailed studies on structure, geology and mineralization in this area, which considered as poorly mapped remote region not only in Egypt but also in Sudan.For these reasons, we integrated image transformation methods include; Principal Components Analysis (PCA), Band Ratios (BR), False-Color Composite (FCC) and filtering on the spectral bands of two distinct datasets ETM + and ASTER for detailed mapping of the NHSZ area. Spectral data fusion with structural data analysis and field observations provide a better understand of the temporal and spatial relationships between the litho-tectonic units and regional tectonic setting in the course of controls on base-metal sulfide and associated gold mineralization. Merging these different data sources in the study area suggests that, the base-metal sulfide and associated gold mineralization are restricted to quartzites, (member of island arc-related metasediments), and mostly controlled by D3 deformational event (main HSZ deformational event). This event characterized by transpressional stress regime, with σ1 trending E–W and σ3 trending N–S, activated conjugate NNW sinistral and NNE–SSW dextral strike-slip faulting, likely during syn-tectonic granodiorite emplacement.

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