Geochemistry of metamorphic-hosted iron ore deposit and associated silica caps in Arıdağ mountain, Bitlis, Eastern Anatolia: preliminary records and pathfinder elements for hydrothermal origin

Authors : Hakan ÇOBAN

Pages : 67-71

Doi:10.17678/beuscitech.609954

View : 21 | Download : 8

Publication Date : 2019-12-27

Article Type : Research Paper

Abstract :Iron ore insert ignore into journalissuearticles values(magnetite-hematite); is one of the common ore deposits occurred in Bitlis and surrounding areas from Eastern Anatolia. A new Fe occurrence have recently been discovered in Mt. Arı insert ignore into journalissuearticles values(locally called as Gultik Mountain); at SE of Bitlis city. Fe ore presents in metamorphic basement rocks as predominantly disseminated-type and to lesser amount massive ore. The area also hosts silica-rich alteration zones. Here, the bulk samples from both disseminated Fe-ore and siliceous alteration zones have been geochemically analysed by XRF method. Obtained results show that the grade of Fe-ore as total Fe2O3 insert ignore into journalissuearticles values(wt.%); increase from 2 wt.% to 42 wt.%, together with MgO insert ignore into journalissuearticles values(from 0.01 to 5.3 wt.%,);, CaO insert ignore into journalissuearticles values(from 0.13 to 1.90 wt.%); and Na2O insert ignore into journalissuearticles values(from 0.42 to 4.93 wt.%);, as a function of decreasing SiO2 insert ignore into journalissuearticles values(from 68 to 39 wt.%); and Al2O3 insert ignore into journalissuearticles values(15 to 8 wt.%);. Significant amount of Co insert ignore into journalissuearticles values(36-160 ppm);, Mo insert ignore into journalissuearticles values(4-13 ppm);, As insert ignore into journalissuearticles values(0.5- 3.7 ppm);, Hg insert ignore into journalissuearticles values(2.3-4.0 ppm); and Sb insert ignore into journalissuearticles values(0.8-1.3 ppm); was determined in analyzed disseminated iron ore samples. Similarly, in the samples of silica caps, SiO2 range between 88 wt.% and 74 wt.%, and decrease with increasing Al2O3 insert ignore into journalissuearticles values(from 0.01 to 20.85 wt.%); and TiO2 insert ignore into journalissuearticles values(from 0.015 to 1.05 wt.%);. Other oxides do not show regular trends. Such siliceous zones also include remarkable amount of Au insert ignore into journalissuearticles values(from 7.8 gr/t to 17.6 gr/t in some samples);, Co insert ignore into journalissuearticles values(30-200 ppm);, Mo insert ignore into journalissuearticles values(2-10 ppm);, As insert ignore into journalissuearticles values(0.9-3.2 ppm);, Hg insert ignore into journalissuearticles values(1.7-6.7 ppm); and Sb insert ignore into journalissuearticles values(0.7-73 ppm); contents. LREE enrichment also exist in high-grade Fe-ore. Based on the first preliminary geochemical results, it is concluded that the metamorphic-hosted Fe ore and Au-bearing silica caps from Mt. Arı have most likely hydrothermal in origin, and leaching of silica and the removal of iron, formed the iron ore insert ignore into journalissuearticles values(hematite-magnetite); in the metamorphic basement rocks. As a new target area, the region has a powerful potential. The uplifting of the metamorphic massif and related postmetamorphic tectonics insert ignore into journalissuearticles values(possibly in Neo-tectonic period); gave way the prominent channels for emplacement of hydrothermal fluids in the area. Due to an episode of regional extensional tectonic, the Au-Co-As-Hg-Sb-Mo-bearing silica-rich hydrothermal fluids relocated into the metamorphic basement.
Keywords : Iron ore, Au bearing silica caps, Hydrothermal origin, Mt Arı, Bitlis, Eastern Anatolia