Vol 72 Iss. 2

Formation analysis of geological and ore formations is increasingly used in geological studies of various kinds, especially in metallogeny. At the same time in the interpretation of such basic concepts as “geological formation”, “magmatic formation” and especially “ore formation”, there are very significant differences ...

Skarn-magnetite deposits owe their appearance to magmatic processes. However, the forms and nature of manifestation of the connection of deposits with magmatism are diverse. The dominant hypothesis, developed by P.P.Pilipenko, A.N.Zavaritsky and their followers, about the formation of skarn-magnetite deposits in the contact zone of intrusive massifs with carbonate sediments ...

In the term “stage” is invested different volume and content. The most justified representations of A.D.Shcheglov and D.O.Ontoev, according to which the stage should be determined by a set of features: the presence of intersections; crushing of formations of early stages and cementation of them with the substance of later stages; interstage dykes of intrusive rocks; temperature of mineral formation; paragenesis of minerals ...

Deposits of the so-called gold-silver formation have been known and developed since ancient times in Bohemia, Transylvania, and Hungary. They are numerous in the west of North and Central America, in Japan, New Zealand, Philippines, Fiji, New Guinea, Sumatra. In our country gold-silver deposits are widespread in the North-East and Far East, in Kazakhstan, Central Asia, they are known in Transcaucasia and Eastern Transbaikalia ...

In carrying out prospecting and exploration work on gold deposits the issue of paramount importance is the identification of areas of ore bodies with high gold content - the so-called ore pillars. But in essence, the geological and economic efficiency of exploration and exploitation is determined to a large extent by knowledge of the regularities of ore pillars location and reliability of forecasting on this basis geological and industrial parameters of the ore body along the strike and dip ...

The deposit is confined to the southern periclinal closure of the anticline, composed of a monotonous thickness of calcareous-clay siltstones and shales. The rocks are characterized by abundance of pyrite and marcasite nodules. The rocks are not characterized faunistically, but lithologically they parallel the Kukkan Formation of the Lower Permian of the unified stratigraphic scheme of the Southern Verkhoyany. The mineralization is localized in crushing and buckling zones of near meridional strike and in quartz veins of near-latitudinal strike. Both have a steep dip at an angle of 70-80°; the zones are westward, and the veins are northward ...

The deposit under consideration is one of the typical deposits of the gold-silver formation. Numerous ore bodies occur mainly among hydrothermally altered acidic and medium-sized rocks of effusive and subvolcanic facies. Explosive formations are widely developed - so-called tuffisites and tuffisite breccias, with which ore bodies are spatially closely associated ...

The dependence of reflectivity and other properties of minerals on their chemical composition has been noted by a number of researchers. It is mentioned, in particular, that the reflectivity decreases with increasing content of magnesium oxide in the composition of magnomagnetites ...

The method of decrepitation is based on the fact that when heating gas-liquid inclusions after their homogenization, even a slight increase in temperature leads to a sharp increase in pressure inside the inclusion. This pressure, as a result of exceeding the strength limit of the mineral forming the walls of the inclusion, causes their rupture ...

Information on the distribution of various modifications of pyrrhotite in ores is of practical interest in connection with the peculiarities of ore dressing and metallurgical processing of pyrrhotite concentrates. Monoclinic pyrrhotite is a ferromagnetic mineral and therefore can be separated by electromagnetic separation in the process of ore beneficiation. In addition, there is information about different flotation properties of monoclinic and hexagonal pyrrhotite, which should also be taken into account in the development of ore beneficiation technology ...

With the massifs of ultramafic, alkaline rocks and carbonatites is associated with a wide range of minerals, many of which are used in various sectors of the national economy. At the same time on these massifs there are a number of minerals, the use of which will become possible in the coming years due to the growing demand for certain types of raw materials and improving the methods of enrichment ...

Studies conducted by the authors during 1973-1975 on gold deposits of the gold-silver formation, allow us to draw certain conclusions and offer specific recommendations on the complex and rational sequence of exploration work at various stages of exploration of deposits belonging to this structural and genetic group ...

The Yuzhno-Belozerskoye deposit, represented by steeply dipping ore deposits hidden under loose strata 250 m thick, was explored by drill holes on a 300x300 m grid with thickening to 150x150 m. In the process of exploitation it was revealed that the shape of ore deposits compared to the detailed exploration data is more variable ...

For a systematic and rational study of the mineral resource base of the country, geological exploration is carried out in successive stages. In this sequence, an important place belongs to prospecting and evaluation works, in the process of which the fields are sorted out and the objects for preliminary exploration are determined ...

Expansion of geological exploration and accelerated development of the mining industry are the most important tasks of the national economy in the 10th Five-Year Plan ...

With the development of metallogenic ideas about the regular, closely related to the peculiarities of the geological structure of the placement of minerals in the Earth's crust prediction of deposits, the allocation of more and more local areas for prospecting becomes one of the most urgent tasks of theoretical and practical geology. This task has long been solved on the basis of the method of analogies, and its mathematical equipment, widely practiced now, does not change anything in its essence ...

Intensive development of manufacture of facing materials from granite is connected with a problem of search of deposits with high enough blockness. For a measure of an estimation of blockness of granites the index called an output of blocks from a rock mass and characterizing, in percent or fractions of unit, the ratio of quantity of blocks (commodity production) to a rock mass from which they are received is accepted