International Geology Review

Mavrin, K.A.

doi: 10.1080/00206817109475570pmid: N/A

The majority views may be generalized as follows: the territorial crystalline base which extends eastward, under the frontal downwarp and the West-Uralian folded region, was formed during the Archean-Early Proterozoic period. Parting of the Uralian geosyncline from the Russian Platform, by downwarping, had begun in the Upper Proterozoic. All the principal structural constituents of the territory were either indicated or formed during the Ordovician-Upper Paleozoic period of its evolution, including the final limits of the frontal downwarp. After Hercynian folding the entire territory subsisted under platformal regime and its exogenic structures were developing in the Meso-Cenozoic period of its evolution. —V.P. Sokoloff.

Poltorykhin, P.I.

doi: 10.1080/00206817109475571pmid: N/A

Extensive recurrent hydrothermal metamorphism, metasomatism, connections of the ores with the minor intrusions, tectono-magmatic considerations, and the fact that total gold content of pyrite, arsenopyrite, and other minerals, stable as it is, tends to increase further, with depth, suggest a high gold potential of the zone and its further exploration. —V.P. Sokoloff.

Artyunyan, R.A.

doi: 10.1080/00206817109475572pmid: N/A

Gold-sulfide ores, auriferous skarns, quartz-carbonate-gold veins, and others on the periphery of the pluton are structurally controlled and genetically related to certain definite intrusions. Their economic potential is believed to be appreciable, pending further investigations. —V.P. Sokoloff.

Krutov, G.A.; Vinogradova, R.A.; Kiseleva, I.A.

doi: 10.1080/00206817109475573pmid: N/A

Accumulations of magnetite ores in contacts of compositionally and chronologically different intrusions, with their different sedimentary host rocks and anomalously high chlorine content of certain minerals associated with the ores, suggest the possibility of a common source of iron in the magnetites and a common source of chlorine in the minerals, with allowances for a degree of assimilation of Fe and Cl from the hosts. The ferruginous Kuvay series at the base of the section may have functioned as the source of iron for the magnetite deposits. Chlorine, an important carrier of iron, under the given conditions may have been borrowed by the magmatic solutions from the saline rocks in the depths. —V.P. Sokoloff.

Golubev, V.S.

doi: 10.1080/00206817109475574pmid: N/A

A mathematical model of infiltrational and diffusional metasomatism, based on equations of the balance of substance and kinetics of the accompanying reactions between the solutes and the rocks, shows that a system of mineralogically different metasomatic zones develops during filtration and diffusion of hydrothermal solutions; in the infiltrational metasomatism, if the reactions are rapid, the interzonal boundaries are strikingly definite, but no such definite boundaries can be developed in the diffusional metasomatism. V.P. Sokoloff.

Titayeva, N.A.

doi: 10.1080/00206817109475575pmid: N/A

The ages of the first and third floodplain terraces at Igarka, on the Yenisey river, were found to be 42,000 and 100,000 years (table 2), using as test materials petrified bones from permafrost rocks in positions where neither adsorbtions nor losses of radioactive elements could have significantly altered their original concentrations in the samples, as happened elsewhere. —V.P. Sokoloff.

Akul'shina, Ye.P.; Pisareva, G.M.

doi: 10.1080/00206817109475576pmid: N/A

Alumina :sodium, potassium :sodium, and (001):(002) ratios, as in hydromicas, increase progressively in the clay fraction of weathered crust, depending on the degree of weathering, regardless of petrographic type of the original rock. Chemical and structural changes caused by weathering are expressed also in mineralogical composition of the clay fraction. The latter relationship is obscured in clays from coastal sediments and is disturbed in marine clays, although the alumina-sodium and the other two ratios are still suited as criteria of “maturity” of the clay substance, in either case. In the case of terrigenic-chemogenic or chemogenic rocks from high-salinity sedimentation basins, neither of the foregoing criteria or relations are found to be valid, because of the masking effect of allothigenic clays. —V.P. Sokoloff.

Materikov, M.P.; Sirina, T.N.

doi: 10.1080/00206817109475577pmid: N/A

Stanniferous ores of quartz-sulfide-tourmaline type in a part of the Delbegetey ore field, within the Kalba zone, resemble the Far-Eastern ones by their geological position, but show no resemblance or kinship with any of Kalba ores. Their cassiterite is relatively high in indium but is almost free from tantalum and Miobium, in contrast with the other cassiterites of Kalba. Their mineralization, imposed as it is onto dikes of the second stage, may have connections with the Semeytau volcanic-plutonic complex, but not with the Kalba granites. —V.P. Sokoloff.

Yendrikhinskiy, A.S.

doi: 10.1080/00206817109475578pmid: N/A

Stratigraphic differentiations and reconstruction of sedimentation cycles (three, in all) show that development of gold placers occurs in early stages of every one of them and that the placer gold is dissipated in the constratal phase of the alluviation. V.P. Sokoloff.

Kashirin, K.F.

doi: 10.1080/00206817109475579pmid: N/A

Both the biotitic and the biotite-pyroxenitic nepheline syenites in the area are chemically intermediate between the agpaitic and the miaskitic types. They are characteristically high in calcium and are much higher in potassium than in sodium. Their Sn, Pb, Zn, Ni, Co, Cr, V, Cu, Ce, La, Nd are about the same as ingranitoids; Sr, Ba, Mo, Rb are much higher; their Li, Y, Te are much lower than the granitoid clarkes. —V.P. Sokoloff.