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A. V. Volkov N. E. Savva A. A. Sidorov V. Yu. Prokof’ev N. A. Goryachev S. D. Voznesensky A. V. Al’shevsky A. D. Chernova 《Geology of Ore Deposits》2011,53(1):1-26
The Shkol’noe deposit is localized in a small granitoid stock, the root portion of which is traced using geophysical data
to a depth of 5–8 km. The high-grade gold ore (33 gpt Au) is enriched in silver and principally differs in ore composition
from the previously studied mesothermal gold-quartz and epithermal gold-silver deposits in the Russian Northeast. The main
reserves of the Shkol’noe deposit concentrate in bonanzas (20% of the total volume of orebodies). The internal deformation
is related to the rearrangement of matter in freibergite; exsolution structures in fahlore and native gold are related to
postmineral metamorphism. It is suggested that the ore of the Shkol’noe deposit occupies a transitional position between porphyrytype
and epithermal levels of ore deposition. 相似文献
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New data on the Paleozoic Ol’cha gold-silver deposit are given, including interpretation of its tectonic setting and mineralogical
characteristization, the most complete to date. Strike-slip deformation is crucial for the formation of the ore field structure. 相似文献
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N. A. Goryachev G. N. Gamyanin V. Yu. Prokof’ev N. E. Savva T. A. Velivetskaya A. V. Ignat’ev 《Geology of Ore Deposits》2014,56(5):322-345
This paper is focused on the Early Cretaceous Ag-Bi-Co-sulfoarsenide mineralization atypical of northeastern Asia, which contains diverse Co-Ni sulfoarsenides, Se-bearing Bi sulfotellurites, and Ag-Bi-Pb sulfosalts. The Upper Seymchan ore cluster is located at the boundary between the Paleozoic Omulevka Terrane of carbonate platform and the In’yali-Debin Synclinorium of the Kular-Nera Terrane. These ore-bearing sequences are represented by the Middle Jurassic terrigenous rocks that rest upon the Upper Triassic sandshale rocks of the upper structural stage. The sedimentary rocks are cut through by high-Al granitic plutons and younger granite-porphyry dikes. The orebodies that are superposed on igneous rocks were formed during (1) the quartz-chlorite-tourmaline stage of metasomatic alteration, (2) the main economic tourmaline-chlorite-quartz-sulfoarsenide vein stage, (3) the polysulfide-quartz stage with Ag, Se, Bi minerals, and (4) the postore quartz-calcite stage with fluorite. The epithermal veins of festoon chalcedony-like quartz with Sb-bearing arsenopyrite occupy a special position. In particular orebodies, the chlorite-quartz ore veins dominate at the upper levels, whereas the quartz-tourmaline veins occur at the lower levels. Wall-rock alteration is represented by metasomatic chloritization and tourmalinization up to the formation of monomineralic metasomatic zones. Sulfides and sulfoarsenides are distinguished by anomalous enrichment of sulfur in the light isotope (δ34S = ?12.8 to ?16.7‰) in contrast to the sulfur isotopic composition of Sb-asenopyrite (?1.7‰) from the genetically different epithermal veins. The oxygen isotopic composition of calcite (the third stage) is uniform at all studied deposits and reveals a tendency to updip enrichment in δ18O within a vertical interval of 200 m. Quartz from ore-bearing and epithermal veins has an almost identical δ18O value (±2‰) but differs from quartz at the tin deposits related to granites of the Canyon Complex and enriched in the light isotope in its oxygen isotopic composition. The mineralization in the Upper Seymchan ore cluster, which is genetically linked to the Early Cretaceous calc-alkaline dike suite pertaining to the period of postcollision late orogenic extension, is formed from magmatic fluids diluted with meteoric water (salinity reaches 20 wt % NaCl equiv) at temperatures varying from 400-380°C to 220-150°C and under a pressure of 970 to 60 bar. The direct vertical mineral zoning is expressed in the change of mineral species with depth and in variable compositions and properties of particular minerals. 相似文献
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Drahomír Chochol Theodor Pribulla Nataly A. Katysheva Sergei Yu. Shugarov Igor M. Volkov 《Astrophysics and Space Science》2005,296(1-4):135-139
UBV RI photometry and 4600–9000 Å spectroscopy of nova V475 Sct taken in the first 3 month after discovery is presented. The object can be classified as a Fe II type slow nova with t 2,V = 48 days, t 3,V = 53 days. The absolute magnitude of the nova at maximum, its colour excess and distance were determined. The observed 13.4 day periodicity of flares can be explained by the mass transfer bursts from the red to the white dwarf, probably caused by the periastron passage of a third body. Two sets of absorptions are seen in the P Cyg-type Hα line profile. They arise in the expanding shell of the nova. 相似文献
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