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Boris Dyachkov, East-Kazakhstan State Technical University (Kazakhstan)
Nina Maiorova, East Kazakhstan State D.Serikbayev Technical University (Kazakhstan)
Tatyana Nikitina, East Kazakhstan State D.Serikbayev Technical University (Kazakhstan)
Nikolay Polyansky, Academy of Mineral Resources (Kazakhstan)
Nurlan Kadenov, "Topaz" prospecting company (Kazakhstan)
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The Kalba area is in the Hercynian Greater Altay which is part of the structure of the Central Asian mobile belt. The Greater Altay was generated during Hercynian oblique collision of the Kazakhstan and Gornoaltay continental margins (C1 - C3). There are four ore belts. Gold and rare-metal deposits are located in the western Kalba and Kalba-Narym ore belts . The western Kalba belt is limited by the Terektinsky and Charsky shear zones with 800 km length, 20-40 km width. The belt is characterized by suboceanic crust , strong gravity gradients and carbonaceous terrigenous and coaly shale rocks and minor andesite-basalts (D1-C1). Ore-forming structures are related to a system of diagonal faults generated in the Zaisan suture zone. Gold ore is genetically connected with small intrusions and dikes of granodiorites and plagiogranites (C3). The major types of deposits are:gold-sulfide-quartz (Suzdal), gold-arsenic-carbonaceous (Bakyrchik) and gold-quartz (Kuludjoun).The Suzdal deposit is very large and is similar to Carlin-sryle gold ore in carbonaceous rocks. the gold ore is located in hydrothermally altered aleurolites and limestones (C1v2-3). The average grade is 10 g/t Au. There is a gold-rich gossan zone. The deposit is currently developed.The Kalba-Narym belt is adjacent to the Irtych rift zone and is limited by deep faults. This belt is 500 km long and 35-40 km wide. Is characterized by negative magnetic anomalies and a regional gravitational minimum. Carboniferous carbonaceous-terrigenous sediments are present (D2-C1), molasse (C2), small intrusions, gabbro-diabase dikes (C2-3) and plagiogranites-granodiorites (C3). The ure is genetically connected with granites of the Kalba complex (P1). Types of deposits are: 1) pegmatite (Ta, Nb, Be, Li, Cs, Sn), 2) albitite-greisen (Sn, Ta), 3) greisen-quartz veins (Sn, W), 4) placers (tantalite, wolframite, scheelite, monazite). The pegmatite deposits have industrial significance (Bakennoe, Belaya Gora, Yubileinoe etc.), and contain pollucite, spodumene, petalite, lepidolite, rubellite etc. The pegmatite bodies form dike systems in granites and slates. Their length is 300-1000 m, width from 4-6 up to 15 m. Main ore minerals are tantalite-columbite, cassiterite, spodumene and beryl. The deposits have been developed but are not mined currently.The formation of gold and rare-metal deposits in the Kalba region will be discussed, and geological models of typical ore deposits will be presented, including criteria for prospecting.
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