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O. D. Komarova 《GeoJournal》1980,4(1):31-44
Some karst regions of Indonesia (Java, Sulawesi, Bali, Madura), on closer examination geomorphologically and hydro-geologically quite distinct from each other, are checked with regard to land-use, settlement and other economic and cultural significance. Brief comparisons are made to similar regions from the Philippines (Bohol), Thailand etc. An amazingly strong differentiation, especially of the rice-cultivation systems, is determined by the varying access to water. Some densely populated limestone regions are suffering even from critical water supply for human consumption, cattle etc. Proposals for improvement and rural development are given. The comparison of agricultural landscape types under changing geo-ecological conditions yield fine examples of closely interwoven man-earth eco-systems. 相似文献
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Shabad T 《GeoJournal》1980,4(1):84-90
Recent demographic trends in the USSR are analyzed using preliminary 1979 census results that were published by the Soviet press in a central report issued on April 22, 1979, and in regional reports issued between April 25 and May 25, 1979. Topics discussed include regional patterns of change in the total population; urban and rural population; trends in the growth of major cities; changes in the sex ratio, particularly in urban areas; and trends in inter-regional and inter-republic migration. 相似文献
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J.W. Schopf T.A. Dolnik I.N. Krylov C.V. Mendelson B.B. Nazarov A.V. Nyberg Yu.K. Sovietov M.S. Yakshin 《Precambrian Research》1977,4(3):269-284
Diverse assemblages of cellularly preserved Precambrian microorganisms have been discovered in cherty stromatolitic sediments from six formations in the Soviet Union: Sukhotungusin Fm. (Middle Riphean, Siberia); Valukhtin Fm. (Middle Riphean, Siberia); Shorikha Fm. (Upper Riphean, Siberia); Minyar Fm. (Upper Riphean, Bashkiria); Olkhin Fm. (Upper Riphean, Siberia); and Chichkan Fm. (Vendian, Kazakstan). These cyanophyte-dominated microbial communities, occurring in both stratiform (cf. Stratifera) and columnar stromatolitic deposits (Baicalia hirta and Conophyton gaubitza), are the first stromatolite-building microbiotas to be reported from the Soviet Union; collectively they comprise more than one-fifth of all such Precambrian assemblages now known. 相似文献
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论述了研究区主要含煤地层的沉积特征。分析了区内童子岩组第三段上亚段沉积环境:3号煤层为河控三角洲相沉积;5号煤层为下三角洲平原型沉积;7号煤层为海湾潮坪型沉积;9号煤层为独立障壁岛泻湖沉积。研究成果对区内煤岩层对比具有重要意义。 相似文献
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114铀矿床地质特征及成矿作用 总被引:1,自引:0,他引:1
114矿床位于南岭伟向构造带大东山-贵东亚带,粤北山字型西翼,系产于碳酸盐岩断裂带中的中低温热液充填交代单铀矿床。铀矿体主要产于石炭纪和二叠纪地层中,受新华夏系北西向张性构造复合早期构造带控制。 相似文献
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华北地台北缘地质构造演化及多金属成矿带的构造控制问题 总被引:4,自引:1,他引:4
华北地台北缘断续分布着一条2000多公里的元古宙多金属矿带。西起狼山群、渣尔泰群、南口群,东至辽北汛河群、辽吉辽河上亚群以至朝鲜境内的摩天岭系均有代表性矿床、矿田和成矿带。矿床皆具层控性,矿化均富集于早一中元古宙地层下部的长英质碎屑岩、沉积一浊积页岩、区域性富磷碳层向白云岩或灰岩的过渡部位。含矿建造厚度大、旋回层次多,含矿性增强。相对深度大、低能的盆地是含矿卤水流集聚的部位。在构造上矿床多处于古裂陷带,特别是古隆起的两侧。多级构造盆地之二、三级盆地较之于陆坡坳陷盆地更利于较大型矿床保存。从而,笔者归结出基本的成矿模型和找矿模型。 相似文献
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陕西金堆城斑岩钼矿床地质特征及成因探讨 总被引:25,自引:4,他引:25
金堆城花岗斑岩在燕山期侵位于元古代熊耳群变细碧岩中,按其岩石化学特征应属高硅富钾的钙碱性系列岩石。钼矿化发育于斑岩体及其外接触带内,矿体由含钼石英细网脉组成,最大矿化深度约达1000m。围岩蚀变自斑岩体向外为:钾化、绢(云)英岩化→硅化→青磐岩化,其中以硅化最为强烈且与钼矿化关系最密切。气液包裹体与含子矿物多相包裹体常常共存,主要成矿温度为300—400℃。硫、氧和碳同位素特征表明,主要成矿阶段的成矿流体是以岩浆水为主的混合液,硫、钼主要来源于花岗岩浆。低f_(o2)、高f_(s2)的弱酸性还原条件以及成矿流体沸腾是辉钼矿沉淀的主要因素。矿床成因类型属斑岩型中高温热液钼矿床。 相似文献
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State formation and nation-building in the Netherlands and the Soviet Union: a historical comparison
Hans Knippenberg 《GeoJournal》1996,40(3):249-262
The interrelated processes of state formation and nation-building are analysed for two cases: the Netherlands (1795–1960) and the Soviet Union (1917–1989). The central question is: how did these states deal with strong cultural (religious or ethnic) cleavages in its societies. In general, there are three options: elimination marginalization, and institutionalization. In both states institutionalization was dominant, but the kind of institutionalization differed very much: personalistic (the Netherlands) versus territorial (Soviet Union) institutionalization. The hypothesis has been put forward that, in general, institutionalization on a personalistic basis will create more political stability. 相似文献
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依据实测的构造要素和盆地分析, 恢复了丰城洛市矿区燕山期以来五期不同体制的构造应力场,讨论了该区构造应力场与滑脱构造形成和发展的关系。 相似文献