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1.
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  相似文献   

2.
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.  相似文献   


3.
High homicide rates constitute a major public health problem in the United States. In the South high rates have been historically conspicuous, and have contributed to the elevated level in the U.S. compared to other countries at a comparable stage of development. This research illustrates the historical persistence of homicide in the South and presents a regionalization of U.S. states based on their quinquennial homicide profiles since 1935. Several social indicators are plotted against trends in lethal violence for the homicide regions. The analysis suggests a pattern of rates declining away from a core region in Alabama and Georgia, and some convergence between the high rates of the South and the increasing rates of other regions. Southern homicide rates remain high in spite of suggestions that cultural differences between the South and other regions have eroded to insignificance.  相似文献   

4.
中国地质学家李四光与当时苏联地学界来往交流紧密,他对地质学的贡献得到了苏联地质学家的高度评价。1958年,苏联科学院全体大会选举李四光为苏联科学院院士,并授予卡尔宾斯基金质奖章;该奖章是1947年由当时的苏联科学院和俄罗斯科学院共同发起的、对地质科学有突出贡献的科学家最高单人奖励,李四光是第六位获奖人,也是至2017年止唯一获此殊荣的外籍地质学家,他的获奖理由是:在地质、古生物、地层和矿产研究工作的综合贡献。李四光有两部著作在苏联被译成俄文出版,分别是1952年的《中国地质学》和1958年的《中国西北部的旋卷构造》,这两部译作对当时的苏联地质界产生了很大影响,极大地推动了李四光学术思想的广泛认知;"地质无国界",中国地调百年的发展历程也有着俄罗斯地学理论、规范、方法实践的烙印,在新的"一带一路"合作倡议和李四光学术精神传承下,中俄、中国与中亚在地学领域的交流合作将不断深化,硕果累累。   相似文献   

5.
6.
Accurate and consistent X-ray fluorescence analysis of major and trace elements using a single pressed pellet for each sample has been achieved with a wide variety of rock compositions. Counting techniques for use with data reduction and correction programs in Standard Fortran IV are described; the latter depend throughout on data developed from a wide range of standard rock compositions. A comparison of ten major and fifteen trace element analyses for U.S.G.S. standard rocks with averages taken from the literature testifies to the precision of these techniques.  相似文献   

7.
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.  相似文献   


8.
Progress report deals with: 1) Geochronology — potassium-argon — principally Precambrian. Gives dates on Precambrian of Baltic Shield including eastern Sweden, Northeastern Norway, Finland, Karelia, and Kola Peninsula. Gives a correlation of the Precambrian for the entire European U.S.S.R. 2) Depth and origin of magmatic ore deposits using reconstructed erosion surfaces for the major periods of mineralization. The depth zones of ore formation of American and European theories is questioned. 3) Tectonic mapping in crustal studies. And in this conjunction 4) Bathy-metric map of the Pacific has been prepared, conspicuous features are major tectonic and volcanic forms of the ocean bottom, as well as minor detail. Brief mention is made of ore deposits from the ocean. 5) “Weathering Crust” studies of subaerial weathering erosion and deposition, mainly of ancient crusts. 6) Study on the origin and distribution of “agricultural areas”, mainly phosphates. 7) Compilation of a Manual of Minerals now underway.--M.A. Klugman.  相似文献   

9.
Flourescence spectral analysis indicates that resinite macerals from Tertiary Hanna Formation coals (Hanna Coal Field, southcentral Wyoming, U.S.A.) can be separated into five distinct groups. The first resinite group fluoresces a a medium green (in blue light); its average spectral maximum occurs at or below 440 mm with a red/green quotient of 0.22. The second resinite group fluoresces yellow-green with an average spectral maximum of 500 nm and a red/green quotient of 0.53. The third resinite group displays a yellow fluorescence having an average spectral maximum of 580 nm and a red/green quotient of 0.86. The fourth resinite group fluorescence orange-brown having an average spectral maximum of 610 nm and a red/green quotient of 1.20. These four groups mostly occur as primary globular resinites exhibiting scratches and fractures, indicating that they are brittle, solid substances. Primary cell-filling and secondary fracture-filling resinites also occur in these four groups. The fifth group only occurs as a secondary void-filling material and lacks evidence of br of brittle properties. It fluoresces a reddish-brown, has a spectral maximum at 690 nm, and a red/green quotient of 1.54. The fifth group has properties resembling exsudatinite. The five resinite groups can be separated on the basis of their nine spectral properties alone, without qualitative petrographic interpretation.The relative quantities of the five resinite groups vary among Hanna Formation coals. The origins of these five resinite groups are probably related to their botanical properties and pre- and post-depossitional conditions. Overall, Hanna Formation resinites have petrographic characteristics similar to other North American resinites; however, only four resinite groups have been distinguished in in certain coals from Utah and New Mexico (U.S.A.), and western Canada.  相似文献   

10.
http://www.sciencedirect.com/science/article/pii/S1674987111001319   总被引:1,自引:1,他引:0  
The microbial diversity in Wuli Area,Qinghai-Tibetan Plateau was investigated using 16S rRNA gene phylogenetic analyses.A total of 117 bacterial and 66 archaeal 16S rRNA gene clones were obtained from the Wuli cold springs.The bacterial clones could be classified into Pwteobacteria,Acidobacteria, Deinococci,Sphingobacteria,Flavobacteria.Nitrospirae,Actinobacteria,Gemmatimonadetes, and unclassified-bacteria;and the archaeal clones could be classified into Crenarchaeota and Thaumarchaeota.Among the major groups,Pwteobacteria and Crenarchaeota were dominant in the bacterial and archaeal 16S rRNA gene clone libraries,respectively.The clone sequences obtained in Wuli cold springs were closely related to those from cold habitats,such as snow/ice/soils on high mountains or at high latitude.Especially,the microbial community composition of Wuli Area was more similar to that in Tibetan glaciers than cold environments of other locations.The data presented in this study have implications for a better understanding of microbial diversity in cold springs on the Qinghai-Tibetan Plateau.  相似文献   

11.
Decommissioning is the inevitable final phase in the life of a nuclear power plant. Research and development to date have been largely technical in nature, despite the substantial past importance of geosocial issues such as emergency preparedness and transboundary pollution. Thus far public inputs have been minor and without measurable effect. Public recognition and the potential for public impact on decommissioning policy is increasing in both countries, although government agencies and utilities are taking little account of it. This article uses experience in the U.S. and Great Britain to address the question of what the geosocial context of nuclear decommissioning is, and how this context will affect nuclear policy. The discussion focuses on four themes: the geosocial ‘signature’ of decommissioning, the emerging interest in decommissioning, decommissioning as the next nuclear leap of faith, and decommissioning as the next focus of nuclear power policy. It is recommended that five areas of public involvement need careful attention: public perceptions, socioeconomic impacts, land use, waste disposal, and economics.  相似文献   

12.
Tufa occurs widely in the Tatar A.S.S.R. and adjacent republics. It is associated with springs escaping from aquifers in deposits of Permian age. No tufa deposits were observed in the region where Jurassic and later deposits are developed. Tufa deposits occur because of a breakdown of calcium bicarbonate to CaCO3, water and CO2. The presence of organic matter and phosphorous inhibits this reaction, accounting in part for the lack of tufa deposition in the other regions. It appears also that tufa deposition is favored by 1) increase of water surface, hence increased evaporation and CaCO3 concentration and 2) slopes where argillaceous material is present.—J.J. Finney  相似文献   

13.
The arsenic concentration in 13 water samples from wells in the thin, alluvial aquifer of the Madison River Valley, Montana, U.S.A. ranged from 26 to 150 μg/l. The Madison River, which originates in Yellowstone National Park, has a mean arsenic concentration of 51 μg/l (σ=26 μg/l), based upon very limited sampling in the study area during the main irrigation period. Groundwater arsenic concentration increases down the valley can be best correlated with the intensity of ditch irrigation in this semiarid area. No other sources of dissolved arsenic as concentrated as that of the river water have been identified. Evaporative concentration of river-derived irrigation water is believed to have been the overwhelming factor in the contamination of this shallow aquifer.  相似文献   

14.
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.  相似文献   

15.
《Applied Geochemistry》1988,3(5):455-474
Formation waters in the Palo Duro Basin, Texas, U.S.A. fall into four major groups based on integrated chemical and isotopic characteristics: (1) interbed brines within the major Permian evaporite aquitard; these are the most chemically concentrated and18O-rich fluids in the basin, and are interpreted as evaporatively concentrated sea water which has been hydrologically isolated since the Permian; (2) brines below the salt on the eastern side of the basin have ClBr, divalent cation, and isotopic systematics indicating a mixture of evaporatively concentrated sea water and meteoric water of δD= −20‰; (3) brines below the salt on the western side of the basin have chemical and isotopic systematics suggesting a mixture of two pulses of meteoric water, one with δD= −20‰ and the other with δD= −55‰; and (4) waters above the salt have the isotopic composition of meteoric waters. Diagenetic alteration of the cation chemistry has occurred for brines within and below the salt. Aquifers below the salt on the eastern side are interpreted as having been charged with dense Permian evaporite brines which subsequently mixed in various amounts with a basin-wide pulse of Triassic meteoric water. On the western side the descending Triassic meteoric waters became saline by dissolution of halite and are currently mixing with a Tertiary pulse of meteoric water initiated by the Laramide uplift to the west. The hydrochemistry suggests flow on the western side of the basin and static conditions on the eastern side. An unrecognized, approximately N-S permeability restriction, or discontinuity in the potentiometric flow surface, is inferred for major aquifers in the central area of the basin.  相似文献   

16.
位于华北地台最北缘的夹皮沟金矿带太古代鞍山群主要由两类双峰式灰色片麻岩组成,其原岩均为TTG类古侵入体夹拉斑玄武岩质暗色包体,岩石化学上与国外许多太古代高变地体中的灰色片麻岩相似,因而不能作为地层来对待。原“鞍山群”可重新划分为白山镇片麻岩、夹皮沟片麻岩和北西向糜棱岩带三大岩石单元,两类灰色片麻岩之间有一些相似处,但也有许多重要差别,可能代表了不同的构造地体。就现有同位素年代数据和野外产状建立了本区主要地质事件的序列。上述岩石单元的划分及主要地质事件序列的建立对本区构造属性的确定及地壳演化的研究有重要的意义。  相似文献   

17.
Yu.A. Isakov 《Geoforum》1984,15(1):89-94
Nature conservation has assumed an increasing importance in the policies of the U.S.S.R., where the geographical diversity of the nation requires a comparable diversity of methods of nature conservation. Emphasis has now shifted from remedial methods to more preventative approaches. Six are particularly important: maintenance of the ecological balance regionally, conservation of renewable resources, protection of the gene pool, conserving ecosystems and geosystems, protection of the natural environment and provision of recreation opportunities.  相似文献   

18.
Mercury inhomogeneity was found between bottles of the same standard for each of the six U.S.G.S. rock standards tested. Variations between bottles amounted to at least a factor of 2 for four of the six standards. Caution is suggested when using these standards as mercury accuracy checks and as estimators of mercury geochemical abundances or cycles.  相似文献   

19.
Recently completed investigations of the crustal structure on ancient shields of the East European platform carried out with the method of “deep seismic sounding” (D.S.S.) have drastically changed the previous notions about the deep structure of shields in general. In the upper crust, in the so-called “granitic” layer, complex anticlinal and synclinal structures as well as numerous faults, thrusts, etc., have been identified. A flattening of steeply dipping seismic interfaces with depth is observed. The crustal thickness in different tectonic zones ranges from 30 to 60 km. It is shown that the M-structure correlates with the sub-surface tectonics in the Ukrainian Shield.  相似文献   

20.
A mobile mass spectrometer to measure He concentrations has been developed by the U.S. Geological Survey. This instrument has been tested in areas of known uranium deposits, and He anomalies have been found in both soil gas and water. A gas sample is collected in a hypodermic syringe, injected into the spectrometer, and analyzed for He. Over 100 analyses a day can be performed with a sensitivity of 10 parts per billion (ppb). One detailed study conducted in Weld County, Colorado, shows that values for He in soil gas can be contoured to outline an anomalous area and that the anomaly is displaced from the deposit in the direction of groundwater flow. Other studies include the Schwartzwalder uranium mine, Jefferson County, Colorado, where He anomalies may be related to geologic structure; near Ambrosia Lake, New Mexico, where the location of He anomalies are related to groundwater movement; and tests for diurnal effects showing only slight variations probably related to soil-moisture content.  相似文献   

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