Prospects of ore-bearing in the Fan-Yagnob syneclise of Zeravshano-Gissar, Central Tajikistan

Background. The Fan–Yagnob syneclise is a large Meso-Cenozoic structure overlapping the Paleozoic folded structure of the Zeravshan–Gissar region of Central Tajikistan. From 1933 up to the present, the conducted geological explorations have identified 81 deposits and 522 ore occurrences. Among them are Jizhikrutskoye and Takfonskoye, which are located in the vicinity of the syneclise under consideration. There are eight mining districts within the boundaries of this metallogenic region, including Fandaryinsky (Au with W, Sn, Mo, Bi), Matchinsky (Sb–W–Au with As, Sb, Bi, Mo, Pb, Zn, Sn, Cu, Ag), Yagnobsky (Sb–W–Sn–Au with As, Sb, Hg, Pb, Zn, Mo, Cu, Bi, Se, Tl, Ag), Varzobsky (W with Sn, Cu, Bi, Zn, Cd, Tl, Se, In, Ag), Iskanderkulsky (Hg–Au with As, Ag), Archamaydansky (W–Bi–Pb–Zn–Sn with Cu, Ag, Au), Shing Magian (Sb–Hg–Ag–Au with As, Zn, Pb, W, Pb–Zn, Bi, Se, Te), Pravoberezhny Zeravshan (Hg–Au with As and Ag). During the Permo-Triassic period, Central Tajikistan underwent intense denudation, during which the depth of the erosion section of the deposits reached about 2 km. The areas of accumulation were the Fan–Yagnob syneclise and other similar structures of the Upper Mesozoic floor. The Fan–Yagnob syneclise was highly likely to accumulate dispersed ore matter from eroded Paleozoic deposits. The article presents facts confirming this assumption.

Aim. The purpose of this study is to substantiate the source of matter from the Paleozoic ore deposits of the Zeravshan-Gissar metallogenic zone for the formation of placer and chemogenic metal concentrations in the Fan-Yagnob Mesozoic syneclise. Research object. The Fan-Yagnob Mesozoic syneclise and the Zeravshan-Gissar Paleozoic mountain-fold region serve as the boundaries of a significant group of ore deposits of various metals.

Materials and methods. The article is based on: 1) publications by our colleagues; 2) the use of a comparative analysis of numerous ore deposits within the boundaries of the Zeravshan-Gissar metallogenic region; 3) rock material selected and analyzed by the authors using a portable X-ray fluorescence spectrometer Vanta-M (Olympus, USA) with a 4-watt Rh anode, 50-kilovolt voltage, and an SDD detector that can detect petrogenic and ore elements with a sensitivity of up to 10^-4%.

Results. The prospects of Mesozoic terrigenous deposits of the Fan-Yagnotsyan syncline for the localization of Paleozoic ore minerals displaced by denudation are substantiated.

Conclusion. The Fan-Yagnob Mesozoic syneclise is an area of accumulation of not only terrigenous and biogenic matter (coal deposit), but also a large group of ore elements that may have practical significance.

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