Summary:
The Taror-Jilau Projects are located in the Zeravshan-Ghizar Inter-arc Basin, the South Tienshan orogenic belt, northern margin of the Tarim-Karakum Plate. The projects are part of Kizilkuli-Alai Mountain, which are of femic-salic fold formation.
Regional strata occur as Silurian-Carboniferous carbonate rocks, sandstone and shale, Jurassic, Tertiary, and Quaternary. Magmatic rocks are developed while granodiorites dominate, and the secondary are diorite and gabbro. Dykes consist of granite-porphyry dykes, porphyrite dykes and quartz veins.
The gold mineralization of Taror Mine is hosted by the skarn rocks between the Devonian and the granodiorite, controlled and altered by the faults.
The Jilau Projects is located in the eastern side of Chinoise granodiorite. Intrusive rocks are part of the Chinoise granodiorite, and they are closely related with the gold mineralization. The gold mineralization is primarily hosted by the intrusive rocks and controlled by faults and joints.
Taror Mine
Exposed strata of Taror Mine primarily consist of the upper Ordovician-lower Silurian Cabelout formation, the middle Silurian Sign formation, the middle Silurian Ludlov formation, the Devonian limestone, the middle Devonian Aifil Majian formation, the Devonian Akbar formation, the lower Carboniferous Donecex and Margu formation.
The lower Jurassic Taror formation, the middle-lower Jurassic Keshtudak, Cretaceous and Quaternary are exposed partially. The gold mineralization is hosted by the skarn rocks between the Devonian and the granodiorite, controlled and altered by the faults.
Intrusive rocks are not well developed and consist of granodiorite. Intrusive rocks in the mine site are controlled by the northwest trending faults and are developed at Carboniferous. The intrusive rocks are closely related with the gold mineralization.
Folds and faults are well developed at Taror mine. The middle linear anticline develops at Hercynian, whose core consists of limestone. The northeast wing consists of silicified shale, and the southwest wing consists of limestone, shale, sandstone etc. The length of the anticline is greater than 1,000 m, striking at 135°, plunging to southeast at the angle of 35°. The northeast wing dips north at the angle of 30–60°, and the southwest wing dips south at the angle of 35–65°.
The anticline is broken by the northwest and nearly east-west trending faults. The intrusive rocks are developed along the core of the anticline. The skarn and gold mineralization occur at the contact.
Metamorphism consists of regional metamorphism, contact metamorphism, and dynamic metamorphism.
Wall-rock alterations are well developed and consist of silicification, beresitization, chloritization, carbonatization, and kaolinization.
Jilau-Olympic-Khirshona Mine
Jilau, Olympic and Khirshona Mine is located at the eastern side of Chinoise granodiorite. Strata occur at the south of Jilau Mine section and east of the mine site. Exposed strata primarily consist of the upper Ordovician-lower Silurian Cabelout formation, the middle-lower Silurian Wanlock formation, the middle Silurian Ludlov formation, the Devonian Akbar formation, and the lower Carboniferous Margu formation. The Cenozoic and Quaternary occur locally. The Wanlock and Ludlov formation are the wall rocks of gold mineralization at Jilau Mine section. Only Quaternary occurs at Khirshona mine.
Intrusive rocks are well developed, occurring as stocks and consisting of Carboniferous medium-fine grained granodiorite, minor diorite and diorite porphyrite dykes. Intrusive rocks in the mine site are part of the Chinoise granodiorite, and they are closely related with the gold mineralization. The gold mineralization is primarily hosted by the intrusive rocks and controlled by faults and joints.
Structures develop at Jilau and Olympic Mine, which can be divided into 4 groups: northwest trending, east-west trending, north northwest trending, and nearly south-north trending.
Metamorphism consists of regional metamorphism, contact metamorphism, and dynamic metamorphism.
Wall rock alterations are developed and consist of silicification, carbonatization, chloritization, epidotization, and kaolinization.
Mineralised Zones
Taror Mine
The gold mineralization of the Taror deposit is hosted by the skarn rocks between the Devonian limestone and the granodiorite. The major mineralisation zones of Taror mine are about 1,000 m in length, from 26 m to 448 m in thickness and from 860 m to 1,715 m in elevation. The mineralisation zones occur in the shape of layer-like, semilunar, plates, or lens. The mineralisation zones strike northwest-southeast, plunge southeast with plunge angle of 35°, and dip southwest with dip angle of 5–45°.
Jilau-Olympic Mine
The major mineralisation zones of Jilau-Olympic vary from 80 m to 620 m in length, from 26 m to 448 m in width, from 1.32m to 124m in thickness, and from 1,495 m ASL to 2,055 m ASL in elevation. The mineralisation zones occur in the shape of tubes, plates, or lens. The mineralisation zones strike from north northwest to north northeast and dip northeast with dip angle of 31–72° at large.
Khirshona Mine
The major mineralisation zones of Khirshona are about 640 m in length and vary from 1,323 m to 1,814 m ASL in elevation. The mineralisation zones occur in the shape of big lens and small veins. The mineralisation zones strike 0–40° and mostly 20° and dip southeast with dip angle of 35–70°.
The mineralisation of Jilau-Olympic-Khirshona gold deposits is mainly hosted by granodiorites, partially by skarns at the contact between limestone and granodiorites at the southeast of the deposit.
The ore types consist of oxidized and primary gold ore, which are separated by at 1,850 m ASL. The mineralogy of wall-rock is similar with the ore. The contact between the wall-rock and the mineralised body is not clearly defined.
Ore minerals in the oxidized ore of Jilau-Olympic-Khirshona gold deposits consist of mainly pyrite, arsenopyrite, scorodite, limonite, conichalcite, natural gold, and malachite, etc. Gangue minerals are mainly quartz, felspar, calcite, chlorite, and kaolin.
Ore minerals in the primary ore of Jilau-Olympic-Khirshona gold deposits consist of mainly pyrite, arsenopyrite, natural gold, limonite, chalcopyrite. Gangue minerals are mainly quartz, orthoclase, K-felspar, calcite, chlorite, and kaolin.
The ore textures consist of xenomorphic, semi-euhedral textures. The ore structures consist of fine veined and fine-veined disseminated structures.
The primary component is gold, silver (‘‘Ag’’), tungsten (‘‘W’’) and copper (‘‘Cu’’), and other accompanying elements include; arsenic (‘‘As’’) bismuth, selenium, and cobalt.
Deposit Types
The deposit type of Taror mine is typical Au-Cu-Ag-As polymetallic contact-metasomatic deposit formed by the interaction of intermediate-acidic magmatic rocks and carbonate rocks. Au-Cu-Ag-As enrichment occurs along the skarn rocks and breccia.
The deposit type of Jilau Mine and Khirshona Mine is of hydrothermal deposit type. Au mineralisation develops along the joints and fractures.