Regional development and the natural resources of the U.S.S.R.

The recent experience of the rising cost of exploiting new material resources in the U.S.S.R. has led to exploration of alternative methods, particularly greater intensification of exploitation. The regional variations in the balance between intensive and extensive methods is considerable and is consequently an important aspect of Soviet geographical research. This paper discusses the criteria and methodology for this crucial economic/resource regionalization of the U.S.S.R.     

Development of geological research in U.S.S.R Academy of Sciences and U.S.S.R. Ministry of Geology and Mineral Reserves

On October 12, 1962, a joint session of the Presidium of the U.S.S.R. Academy of Sciences and the Collegium of the U.S.S.R. Ministry of Geology and Mineral Reserves adopted a resolution “On the present state of the geological sciences in the U.S.S.R. Academy of Sciences and the U. S. S. R. Ministry of Geology and Mineral Reserves and their prospects for the future.” Important contributions of Russian geologists are acknowledged, but attention is drawn to many shortcomings. Future goals of geological study and work are given in detail. Twenty-one lines of research to be concentrated on are given, covering all phases of geology, geophysics, and geochemistry. In discussing the failings of the geological profession in Russia, it is of interest to note the following comment: “Geological research in other countries is still insufficiently studied and applied, and we are not making adequate use of geologic information from abroad.” The list of the Russian geologists' shortcomings sounds vaguely familiar. —J. R. Hayes     

Possible evidence for regional chemical heterogeneity of the Upper Mantle

The garnets of garnet-peridotite xenoliths that occur in the kimberlites of Southern Africa and the U. S. S. R. are shown to differ significantly in chemical composition. It has been demonstrated that the compositions of garnets of this type depend largely on the compositions of the media in which they grew (Rickwood, Mathias and Siebert, 1968), and thus it is concluded that the Upper Mantle in these two regions differs in chemical composition. Southern Africa is a chromiferous province and the U. S. S. R. is a ferric province.South African U.M.P. Publication No. 15.This paper was commenced whilst I was financed by the C. S. I. R. Upper Mantle Committee and is a contribution to the South African part of the Upper Mantle Project.     

Thermal waters in the U.S.S.R.

A very interesting and informative paper on widespread occurrence of a thermal hydrosphere. Geothermal power uses are discussed. Distribution of heated waters, some up to 150° C is discussed in considerable detail, especially with reference to possible power utilization of the geothermal energy. Seven hydrothermal regions of the U.S.S.R. are discussed and delineated. Chemical quality of waters is referred to. There is a summary listing of locations in the U.S.S.R. where thermal waters could be utilized for generation of electric power. — B. N. Cooper.     

FORMATION OF COAL DURING THE CRETACEOUS PERIOD AND ITS ROLE IN THE GLOBAL PROCESSES OF COAL ACCUMULATION

P. I. Stepanov suggested that during the Cretaceous there probably took place a considerable accumulation of coal, although that time was always considered to have been a period of attenuation of coal accumulation. The analysis of facies of the Cretaceous deposits in the far east maritime region of the U. S. S. R. as well as of those of Alaska led the author to conclude that coal accumulation during the Cretaceous was tremendous. This conjecture has now been confirmed: the new estimate of coal reserves of the U. S. S. R. has shown the Cretaceous Lena coalfield to be the largest in the world. Tremendous reserves of coal are also concentrated in the Bureya, Maritime, Anadyr and Sakhalin Cretaceous coal bearing basins of the U. S. S. R. in the Ryōseki basin of Japan and in the Cretaceous coal deposits of North America, particularly in Alaska where a major coalfield very likely exists. Thus it may now be considered that during the Cretaceous there accumulated reserves of coal comparable in immensity to those accumulated during the Tertiary and undoubtedly much larger than those of the Permian, Carboniferous and Jurassic. It may be asserted that rate of coal accumulation kept ever increasing in the course of geological time, and the Cretaceous may be regarded as a period of very intensive coal accumulation. Following up Stepanov's idea we can point out the knots of Cretaceous coal accumulation: Lena, Alaska, Anadyr, Sakhalin — Maritime. The new data on the Cretaceous coal accumulation should be taken into account in any reconstruction of the history of geological development of the earth and of the evolution of the organic world. --Author's English Summary.     

Geochemical characteristics of central Chile (33 °–34 °S) granitoids

Seventeen granitoid samples from batholiths in central Chile (33 °–34 ° S) have been analyzed for trace element content. The samples range in age from Paleozoic to Tertiary, and in rock type from quartz diorite to granite. In general, compared to andesites from central-south Chile these rocks are more siliceous with lower abundances of compatible trace elements and higher abundances of incompatible trace elements. However, Upper Tertiary granodiorites have important geochemical similarities, such as highly fractionated rare-earth element (REE) distributions relative to chondrites, to some modern andesites in this region; e.g., Marmolejo. Similar highly fractionated REE distributions are also common in the cores of zoned intrusive sequences in the Sierra Nevada of the western U.S. Based on limited sampling of central Chile Cretaceous and Tertiary plutonics, there may be a west to east increase in light REE/heavy REE ratio and in Sr content. Compared to the Upper Tertiary granodiorites, the Paleozoic granodiorites have similar REE abundances but lower Sr, Sc, Cr, Co, and Ni contents.     

Brittle tectonic structures and palaeostress analysis in the Isle of Wight,Wessex basin,southern U.K.

Brittle tectonic analysis of Cretaceous–Paleogene sediments at a total of 17 sites located in the Isle of Wight (U.K.) enables four main tectonic events that occurred prior to and after the folding to be identified and successive palaeostress tensors to be determined using the inversion method. Three of the events can be shown to have occurred prior to the folding: (1) a syn-sedimentary extension of Upper Cretaceous age; (2) a strike-slip faulting regime with an ESE–WNW direction of compression; (3) a compressional regime, marked by strike-slip faulting, with an NNE–SSW to N–S direction of compression. The fourth and last compressional event took place after the folding and is characterised both by reverse and strike-slip faulting, with a dominant N–S direction of compression. Syn-folding faults also developed between the third and fourth events. All four events can be connected to the extensional tectonics and different steps of structural inversion, both of which were integral to the development and evolution of the Wessex basin.     

Decisions of the Standing Stratigraphic Commission on Ordovician and Silurian of U.S.S.R.

The Committee on Ordovician and Silurian Stratigraphy of the U. S. S. R. defines a number of time-stratigraphic subdivisions of the Russian Ordovician and Silurian Systems. — C.G. Tillman.     

Structure of the earth''s crust on the territory of the U.S.S.R.

The compilation of statistical data for 269 seismic crustal sections (total length: 81,000 km) which are available in the U.S.S.R. has shown that the preliminary conclusions drawn on relations between the elevation of the surface relief and Bouguer anomalies on one hand and crustal thickness (depth to the M-discontinuity) on the other hand are not fulfilled for the continental part of the U.S.S.R. The level of isostatic compensation has been found to be much deeper than the base of the earth's crust due to density inhomogeneities of the crust and upper mantle down to a depth of 150 km.

The results of seismic investigations have revealed a great diversity of relations between shallow geological and deep crustal structures:

Changes in the relief of the M-discontinuity have been found within the ancient platforms which are conformable with the Precambrian structures and which can exceed 20 km. In the North Caspian syneclise, extended areas devoid of the “granitic” layer have been discovered for the first time in continents. The crust was found to be thicker in the syneclises and anteclises of the Turanian EpiHercynian plate. In the West Siberian platforms these relations are reversed to a great extent.

Substantial differences in crustal structure and thickness were found in the crust of the Palaeo zoides and Mesozoides. Regions of substantial neotectonic activity in the Tien-Shan Palaeozoides do not greatly differ in crustal thickness if compared to the Kazakhstan Palaeozoides which were little active in Cenozoic time. The same is true for the South Siberian Palaeozoides.

The Alpides of the southern areas in the U.S.S.R. display a sharply differing surface relief and a strongly varying crustal structure. Mountains with roots (Greater Caucasus, Crimea) and without roots (Kopet-Dagh, Lesser Caucasus) were found there.

The Cenozoides of the Far East are characterized by a rugged topography of the M-discontinuity, a thinner crust and a less-pronounced “granitic” layer. A relatively small thickness of the crust was discovered in the Baikal rift zone.

The effective thickness of the magnetized domains of the crust as well as other calculations show that the temperature at the depth of the M-discontinuity (i.e., at depths of 40–50 km) is not higher than 300–400° C for most parts of the U.S.S.R.     

Seismic studies of low-velocity layers and horizontal inhomogeneities within the crust and upper mantle on the territory of the U.S.S.R.

Recent seismological studies of low-velocity layers in the U.S.S.R. have led to the development of new methods of investigation. The most important results obtained are presented in this paper. Several new techniques of record treatment and advanced computer programs make it possible to solve two-dimensional problems of seismic wave propagation in complex media and to outline zones of velocity inversion in the crust and mantle of many regions in the U.S.S.R.Zones of this type seem to occur only locally and are typical of some particular geostructures. Lateral inhomogeneities are also found to be closely related to geological features. Their depths sometimes can reach 300–400 km.     

Crustal investigations of the U.S.S.R. by means of earthquake-generated converted waves

The method of earthquake-generated converted waves which is based on the simultaneous recording of longitudinal (P), transverse (S) and converted (PS and SP) waves has been used in the U.S.S.R. since 1956. Converted phases generated at crustal and upper-mantle discontinuities in the seismic focal area are carefully analyzed. In this paper some dynamic characteristics of transmitted PS- and SP-waves arising at different types of boundaries are described.

From a comparison of the properties of the recorded converted waves with the results of theoretical computations conclusions can be drawn with regard to the possible structure of the “exchange” (conversion) boundaries. Seismic cross-sections are presented which illustrate the high effectiveness of the method in regional investigations of crustal structure. Owing to its significance and the multitude of observations (over 22,000 km of observation lines) the method is one of the principal seismic techniques used in the U.S.S.R. which give quantitative information on crustal layering.     

Decisions of the Standing Stratigraphic Commission on Paleogene of U.S.S.R.

The committee on the Paleogene of the U. S. S. R. presents a tabulation of the lithologic and faunal characteristics of a complete Paleogene section in the Crimea. The Committee proposes that this section serve as a new type of section for the Paleogene of Europe. — C.G. Tillman.     

Socio-economic geography in the U.S.S.R.

A major field of research since the 1920s has been methods and theories of economic regionalization. The territorial-production complex is now recognized as a key developmental tool within the framework of economic-planning regions. Recently, there has been a more marked growth of study into problems of natural-resource development, social progress and change in the U.S.S.R. as well as into the spatial structure of other nations, particularly other socialist countries and non-socialist developing countries.     

The Santonian-Campanian reversed polarity magnetozone and the Late Cretaceous magnetostratigraphical time-scale

Magnetostratigraphical data on the Late Cretaceous Magnetic Quiet Zone (normal geomagnetic polarity zone Jalal) are reviewed. This zone was first defined by Shmeleva (1963) in deposits of the Fergana Ridge (U.S.S.R.), and was there found to contain a reversed (R) magnetozone, named the Kuldja, which was traced to various regions of the U.S.S.R. The Kuldja zone corresponds to magnetozone Gubbio A — defined at Gubbio (Italy). Palaeontological data suggest that it spans the boundary between the Santonian and Campanian stages.     

Sedimentary provenance of the Hengyang and Mayang basins,SE China,and implications for the Mesozoic topographic change in South China Craton: Evidence from detrital zircon geochronology

Detrital zircon U–Pb data from sedimentary rocks in the Hengyang and Mayang basins, SE China reveal a change in basin provenance during or after Early Cretaceous. The results imply a provenance of the sediment from the North China Craton and Dabie Orogen for the Upper Triassic to Middle Jurassic sandstones and from the Indosinian granitic plutons in the South China Craton for the Lower Cretaceous sandstones. The 90–120 Ma age group in the Upper Cretaceous sandstones in the Hengyang Basin is correlated with Cretaceous volcanism along the southeastern margin of South China, suggesting a coastal mountain belt have existed during the Late Cretaceous. The sediment provenance of the basins and topographic evolution revealed by the geochronological data in this study are consistent with a Mesozoic tectonic setting from Early Mesozoic intra-continental compression through late Mesozoic Pacific Plate subduction in SE China.     

GEOBOTANICAL MAP OF THE U.S.S.R.

A newly compiled geobotanical map of the U.S.S.R. scale 1:4,000,000 is described. Two hundred and ten categories of vegetation are mapped, classified under 15 major groups. The relation of the mapped vegetation units to climate, soil, ground condition (permafrost), watersheds, and major geomorphic features is emphasized. -- M. Russell.     

尼雄地区早白垩世磁铁矿伸展成矿地质背景及成矿模型

尼雄地区早白垩世磁铁矿以成矿岩体及矿床研究偏多,忽略围岩时代及其成矿地质背景分析。尼雄早白垩世磁铁矿可分为矽卡岩型和热液脉型,而达及藏布地区热液脉型磁铁矿与基性岩脉密切相关,通过共生辉长岩岩脉锆石U-Pb年龄(120.1±1.7 Ma)限定热液脉型磁铁矿成矿时代约120 Ma,与已经确定成矿时代的矽卡岩型铁矿成矿时代一致,指示尼雄矿田两种类型磁铁矿受控于相同的地质背景。通过尼雄岩体碎屑岩围岩(原上二叠统敌布错组)碎屑锆石测年,获得其沉积时代介于130～120 Ma之间,故将上二叠统敌布错组重新厘定为下白垩统则弄群。结合区域地层及岩浆岩新资料,认为冈底斯中部则弄群火山岩与侵位于其中的岩体构成一个早白垩世火山-侵入杂岩体系,其与尼雄矿田早白垩世磁铁矿密切相关。该早白垩世火山-侵入杂岩地球化学特征及尼雄附近浅表层次构造共同指示冈底斯中部在早白垩世处于伸展构造背景。最后,依据伸展构造背景新认识建立了尼雄地区早白垩世磁铁矿成矿地质模型。     

New Xyelidae (Hymenoptera) from the Mesozoic of Asia

The article is a survey of the higher classification of the Xyelidae (Insecta: Hymenoptera) as well as two new tribes and twelve new genera being described. Fossils that form the basis of this work are from the Upper Triassic (?) (Kirgizia), Upper Jurassic (South Kazakhstan), and Upper Jurassic or Lower Cretaceous (Vitim river, Baysa area). -- R. W. Hodges.     

Peculiarities in the deep structure of the Sakhalin-Hokkaido-Primorye zone

The results of detailed seismic crustal investigations in the marginal part of the transition zone from the Asian continent to the Pacific Ocean are discussed. The observations were carried out during 1963 and 1964 by expeditions of the Institute of Physics of the Earth of the U.S.S.R. Academy of Sciences and the Sakhalin Complex Research Institute, Siberian Division of the U.S.S.R. Academy of Sciences. The results of these measurements have been described in detail in a monograph, by Zverev and Tulina, entitled Deep Seismic Sounding of the Earth's Crust in the Sakhalin-Hokkaido-Primorye Zone (1971).

The distribution of seismic crustal characteristics is studied and schematic maps of the surface of presumably Cretaceous and Meso-Paleozoic (or pre-Paleozoic) sediments near Sakhalin Island as well as of the mantle surface in the Sakhalin-Hokkaido-Primorye zone are presented.