Investigation for gold and base metals mineralization and petrochemical characteristics of the rocks of Golo Das and surrounding areas, District Ghizar, Gilgit-Baltistan, Pakistan
Keywords:
Gold and base metals; Petro-chemistry; Volcanic and plutonic rocks; Golo Das; Gilgit.Abstract
Panning of stream sediments for gold along Indus River and its tributaries in the northern areas of Pakistan is being carried out for decades but the source rocks for gold are still unknown in the region. The interpretation of geochemical exploration data obtained by various geological organizations and the Remote Sensing studies conducted in the region have identified five areas for follow-up studies for gold mineralization in the Gilgit-Baltisatn region. Among these, Golo Das and surrounding areas have been investigated for gold mineralization along sulfide-bearing sheared / alteration zones during this study. The rocks exposed in the study area are highly deformed and include basalt-andesite sheet dominant volcanics and un-deformed volcanic rocks of Ishkoman Volcanic Center / Teru Volcanic Formation of Ghizar Formation and diorites of the Kohistan batholith. These rocks in Golo Das and surrounding areas are explored for their petrochemical characteristics and productive nature for gold, silver and base metals mineralization associated with sulfide-bearing sheared / alteration zones. Results of this work confirm enrichment of copper, cobalt, gold and silver in these alteration zones by hydrothermal processes but not in high concentrations to be of economic level. On the basis of major and trace element chemistry and the enrichment in large ion lithophile elements relative to high field strength element with well-defined negative Nb anomaly the rocks of the study area are comparable to the subduction related calc-alkaline rocks of island arc type setting. These rocks are, therefore, displaying subduction related signature and are considered a part of the Cretaceous Kohistan island arc.
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