Vol 11 Iss. 1

The purpose of this article is the mineralogical study of the Khalilovsky nickel-hydrosilicate deposits. Along with this, the author examined chromite and magnesite deposits. As a result of geological observations, a geological map and sketches were compiled. Chromite itself and holocrystalline magnesite are unknown in Khalilov. Minerals of chromium and salts of magnesium carbonate are represented by completely different mineral species. Therefore, their deposits are named in a broader sense, namely chrome spinels and magnesian carbonates. There are 25 elements known in the Khalilovsky massif: H, K, Na, Mg, Ca, Sr, Ba, Ag, Au, Pt, Zn, Cu, Fe, Ni, Co, Mn, Cr, Ti, V, As, P, Si, Zr(?), C, S. Of these, the content of noble metals is noted spectrally; Zn, V — in traces, Sr, Ba — in hundredths of a percent.

In connection with the identified new scheme of the geological structure of the Soviet Tien Shan, all the volcanic processes of the latter are rejuvenated. In confirmation of this, we observe the appearance of basalts among the Tertiary sediments in the valley of the Naryn River, discovered by S. S. Shultz, granite aplites in the Dzhemandavan ridge, found by O. I. Sergunkova, cutting through the Tertiary Naryn salt-bearing formation, the deposit of cockade lead ores described by I. I. Bezdeka in the Akshiyryak ridge among Quaternary conglomerates, etc. All this suggests that it is necessary to set as a priority task to review all manifestations of volcanism within the Tien Shan, and not only of Alpine tectogenesis, but also of more ancient periods of its manifestations. This question is not only of purely scientific, but also of great practical importance, as it makes it possible to expand the base of searches for various minerals associated with intrusions, both vertically and in area. All those deposits that were previously considered characteristic only of the “central arcs” of the Tien Shan can now and should be discovered in the “northern arcs” of the latter, such as deposits of mercury, antimony, arsenic, radioactive ores, etc.

One of the remarkable features of the geology of the Chiatura manganese deposit is the presence of different facies of ore-bearing sediments. Of particular interest is the change in these facies in the vertical section of the manganese ore strata, which was well traced both from outcrops and from numerous drill holes. Analysis of the geological structure of the formation of ore-bearing sediments and host rocks led to the conclusion that the vertical change of facies depended on the orogenic movements that took place at the time of formation of the manganese ore strata. A very interesting fact was that within the area of the Chiatura deposit, which occupies an area of about 100 sq. km, the amplitude of these movements in different parts of it was apparently unequal, which affected the mineralogical composition and structure of various facies. The proposed work contains a brief summary of the main provisions relating mainly to this phenomenon, almost unknown in the literature, among sedimentary ore deposits. There is reason to assume that changes in the composition of facies in the vertical section in the Oligocene deposits of the Chiatura region were caused by orogenic movements, which were the last echoes of the pre-Oligocene orogenic phase.

The Bukachacha field, located in Eastern Transbaikalia (coordinates 53° N and 116°50' E), attracts attention for three reasons. Firstly, among other Mesozoic spots basins in Transbaikalia, it has undergone has been subjected to the most detailed geological investigations research , and therefore the results of work on it there make it possible to outline a methodology for studying similar uch deposits, which has not yet been sufficiently developed; secondly, because its study sheds light on the genesis of Upper Jurassic deposits and tectonics; and, thirdly, because the deposit has sintering coals, which sharply distinguishes it from other brown coal deposits in Transbaikalia. The coal-bearing deposits of the deposit field cover occupy an area of about 40 km², their bounded aries are by the Sarananda and Kudikhta rivers. The cCoal-bearing deposits are surrounded by hills of crystalline rocks, and the boundary of their distribution coincides with the boundaries of the valley. These contours, iIn addition to their natural contours, determined by outlines, due to the differing ent hardness of the crystalline rocks and the coal-bearing deposits, were these boundaries hae been established by exploration workings, the lines of which intersect the deposit at a close distance intervals from each other, and these lines in places extend onto the granites. There are no natural outcrops of coal-bearing sequence trata in the area, and all data on its occurrence and composition were have been obtained on the basis of from mine workings.

Kopet-Dag is a mountainous region, poorly studied geologically. The question of a clear understanding of the tectonic structure of Kopet-Dag is of enormous importance for determining the regime of groundwater, the direction of its flows, quantity, area of distribution, etc. The problem of water in Turkmenistan has always been one of the most important, and now in connection with the socialist reconstruction of Ashgabat, the development of industry and cotton crops in the Kopet-Dag region, it is of particular importance. An accurate understanding of the true tectonic structure of Kopet-Dag is also required in order to find the place and role of the latter on the tectonic background of the vast territory embracing the folded regions of southern and northern Iran, Armenia, the Caucasus, Mangyshlak and Emba. This will undoubtedly bring clarity to the understanding of the nature of the relationship between Kopet-Dag and the Karakum depression and will be the necessary material for solving the most important practical problem of Turkmenistan regarding the direction of the continuation of the Western Turkmen oil strip.

These emerald mines are situated on the Eastern slope of the Urals, 70 kilometers NNE of Sverdlovsk town. The deposit is a complex of metamorphic rocks enclosed by three intrusions, viz.—on the E, by an intrusion of porphyritic granite, on the W, by one of granite, on the E, by the so-called "Eastern“ intrusion — complex and strongly differentiated. The metamorphic complex presents a thick layer of amphibolites and plagioclasehylobites, wherein are included lens-like talcous rocks. In the nuclei of the latter are often to be found remnants of serpentinites and sometimes of peridotites and dunites. In these lenses, through injection of divers vein substrates, have been formed deposits of emeralds, beryl, and fluorite. Porphyritic granite (fig. 1) and granite (fig. 2) are in the main similar rocks. They are made up of quartz, feldspar, and plagioclase, with an insignificant admixture of micas (p. 198). This comparison clearly shows that these two rocks having a great general resemblance greatly differ in details. Therefore it is impossible, to my opinion, to unite them into one integral whole neither from the point of view of their composition nor from the conditions and time of their formation. On the contrary one must recognize that these two rocks are different in all respects.