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The Kayenmyvaam prospective district is situated in the Western Chukchi Peninsula, Russia. It includes 4 main prospects: Arykevaam, Televeem, Levy Kayen and Sredny Kayen hosted by the Upper Cretaceous volcanic rocks of the Okhotsk-Chukchi Volcanic Belt (OChVB). Ore bodies are associated with N, NW and NE trending faults. LS epithermal mineralization is predominant in the area, but there are also evidences of porphyry-style one (IS epithermal mineralization). Ore bodies occur as quartz or quartzite veinlet systems. Major alteration types are propylitic, argillic and advanced argillic. High grades of main components were determined in ore samples: over 500 ppm Au, 0.4% Ag, 4.8% Cu, 0.2% Mo, 0.5% Zn, 1.9% Pb and >0.2% Te. Gold-silver ratio varies from 10:1 to 1:300. Geochemical anomalies are widespread and their composition corresponds to the one of hypogene mineralization (Au, Ag, Mo, Cu, Pb, Zn, and others). Gangue minerals include quartz, adularia, chlorite, kaolinite, gypsum, hydromica and calcite. Ore minerals are pyrite, galena, sphalerite, chalcopyrite, bornite, gold, electrum, polybasite-pearceite, acanthite, molybdenite, proustite-pyrargyrite, hessite, petzite, altaite and tetrahedrite-tennantite. Fluid inclusions homogenization temperatures vary from 136 to 369ºC, salinity is within the range of 0.2-1.4 wt. % NaCl equiv. Pressures estimated for fluid boiling at the temperature of 240-327ºC are 3-12 MPa and correspond to the ore formation depth of 0.1-0.5 km. The Arykevaam is the silver prospect with low resource potential, so is the gold-silver prospect Levy Kayen. Main gold prospects are Televeem and Sredny Kayen. Ore minerals in the Televeem prospect are similar to those of the Sentyabr'sky gold-silver prospect in the Dvoynoy District. [ABSTRACT FROM AUTHOR]

The Ugatkin paleo caldera is situated in the external zone of the Okhotsk-Chukchi volcanic belt. There are three volcanic units representing contrast volcanic rocks. The oldest unit is composed of andesitic tuff and lavas. Middle aged rocks are rhyolitic lavas and ignimbrites. Acid obsidian unit is the youngest. Subvolcanic rocks are represented by rhyolites, andesites and basalts. There are several zones with silver LS and polymetallic mineralization in the caldera. Samples were analyzed by ICP-MS and XRF. The composition of rocks is typical of calc-alkaline series formed in island arc setting. The rocks are enriched in light rare earth elements ((La/Lu)n = 2.4-11.3) that indicates homogeneity of the magmatic source. The rocks are characterized by the depletion of Eu ((Eu/Eu*)n = 0.6 - 1) which is due to incomplete melting of the source plagioclase. [ABSTRACT FROM AUTHOR]

The Kapelka Ag-Au prospect is located in the Western Chukchi Peninsula, Russia. The mineralization is hosted by Upper Cretaceous volcanic rocks of the Okhotsk-Chukchi Volcanic Belt (OChVB). Wallrock alteration and ore bodies are associated with NE and NNE trending faults. The LS and base metal types of mineralization are predominant at the Kapelka prospect. Ore bodies occur as stockwork and veinlet systems. Major alteration types are propylitic, argillic and secondary quartzite. High grades of main components were determined in ore samples: 1.5% Ag, 12% Pb, 2.2% Cu, 0.8% Zn and 27 ppm Au; gold silver ratio is from 1:100 to 1:3500. The anomalous geochemical field is widespread. The composition of secondary halos is corresponding to the one of primary ore. Propylites are composed of epidote, chlorite, K-feldspar, quartz. The main minerals of argillic rocks are tosudite, montmorillonite, dickite and quartz. Propylitic and argillic rocks were formed at the temperature of 330-365 and 110-300°C respectively (the Cathelineau thermometer [1]). Gangue minerals include quartz, adularia, sericite and others. Ore minerals are pyrite, arsenopyrite, galena, sphalerite, chalcopyrite, bornite, electrum, polybasite-pearceite, acanthite and tetrahedrite-tennantite. Native silver, acanthite, anilite, brochantite, anglesite, cerussite, malachite, azurite and wulfenite represent supergeneous assemblage. Homogenization temperatures of fluid inclusions vary from 167 to 353°C, salinity is within the range of 0.2-1.4 wt. % NaCl equiv. Pressure estimated for fluid boiling at the temperature of 353ºC is 16MPa corresponding to the ore formation depth of 0.6 km. According to geology, wallrock alteration and composition of geochemical anomalies, the closest analogue of Kapelka is the Zhilny prospect nearby the large Au-Ag epithermal Valunistoye deposit, the Eastern Chukchi Peninsula. Future exploration will clarify the parameters of the ore bodies and economic prospects of Kapelka. [ABSTRACT FROM AUTHOR]