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81.
Abstract. The Rodnikovoe gold deposit situated in a presently active hydrothermal system located north of the Mutnovsko-Asachinskaya geothermal area in southern Kamchatka, Far Eastern Russia, consists of typical low-sulfidation quartz-adularia veins in a host rock of diorite. The age of the mineralization was dated by the K-Ar method as 0.9 to 1.1 Ma based on adular-ia collected from the veins. Representative ore minerals in the deposit are electrum, argentite, aguilarite, polybasite, pearceite and lenaite. Dominant alteration minerals are adularia, α-cristobalite, chlorite, illite and kaolinite. Hydrothermal solutions of neutral pH were responsible for the mineralization, which is divided into six stages defined by tectonic boundaries. Gold mineralization occurred in stages I and III. Hydrothermal brecciation occurred during stages III, IV and VI. Stages II, IV, V and VI were barren. The estimated ore formation temperature based on a fluid inclusion study is 150 to 250 °C at a depth of approximately 170 m below the paleo-water table. Boiling of hydrothermal fluids is hypothesized as the cause of the intermittent deposition of gold ore. The sulfur and oxygen fugacities during the deposition of anhydrite prior to the hydrothermal brecciation were higher than those during the gold mineralization stages. The occurrence in the hydrothermal breccia of fragments of high grade Au-Ag and polymetallic ores suggests that higher grade mineralization of these metal ores might have occurred in a deeper portion of the deposit.  相似文献   
82.
The World Summit on Sustainable Development (26 August–4 September 2002), held in Johannesburg on the tenth anniversary of the first Earth Summit, provides the opportunity to reflect on the meaning of the sustainable development concept. This paper uses the case study of the Russian Federation to explore the relationship between official interpretations of sustainable development and alternative understandings concerned with the betterment of humankind, which draw on Russia's cultural and scientific heritage. It is suggested that there is much to be gained from reopening the sustainable development debate to incorporate such cultural particularities, both at the national and international levels.  相似文献   
83.
李宇  孟丹  叶海鹏  张宁  郑吉  李飞  董锁成 《地理研究》2021,40(11):2967-2985
本研究以社会经济发展统计数据和多源遥感影像数据为基础,通过决策融合遥感解译方法、多元离散回归模型、质心迁移、扇形分析法等,重点考察了伊尔库茨克(Irkutsk)、新西伯利亚(Novosibirsk)、叶卡捷琳堡(Yekaterinburg)分别在1990年、2000年、2010年、2018年城市不透水面的扩张特征,探讨了不同城市扩张的自然环境变化与社会经济发展耦合作用与驱动机制。首先不同城市的扩张方向、强度、速度、模式上存在显著时空差异,三个城市分别呈现“快速增长-增长-慢速增长”“增长-增长-慢速增长”“慢速增长-增长-慢速增长”发展趋势,其中叶卡捷琳堡扩张强度最高。而城市新增不透水面的扩张类型以蔓延式和跳跃式扩张为主,填充式扩张所占比重较小。其次典型城市扩张主要发展方向不同,伊尔库茨克城市扩张特征由南北发展向转为放射状发展,新西伯利亚由东西向发展向正西方向发展,叶卡捷琳堡城市扩张特征由放射状发展向西南方向发展,其发展方向与其自然、区位以及社会因素有关,其中自然因素和区位因素是俄罗斯三类典型城市扩张的主导因素。最后文章阐述不同类型的俄罗斯城市其发展方向与城市发展潜力,为其同类型城市发展提供科学管理依据。伊尔库茨克借助丰富旅游资源重视城市内旅游产业发展,新西伯利亚由于历史问题,对城市内外部交通网络布局提出更高标准规划,叶卡捷琳堡作为俄罗斯国内较发达城市,可加强和周边城市联系形成具有联动作用的城市群。对中国东北地区同类型城市发展规划有着一定的启示意义,包括加强发展紧凑城市、注重交通设施建设、加强周边城市联动、发展旅游等。  相似文献   
84.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns (Cyatheaceae,Dicksoniaceae,Osmundaceae), Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns (Cyatheaceae,Dicksoniaceae), Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dieksoniaceae);the Aptian one by ferns(Cyatheaceae,Dieksoniaceae,Gleicheniaceae)and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae)and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   
85.
The changes of taxonomical composition of the Late Jurassic-Early Cretaceous palynofloras are revealed,in the upper stream of Bureya River in Bureya Basin.The palynofloras are dominated as follows:the Berriasian one by ferns(Cyatheaceae,Dicksoniaceae,Osmundaceae),Classopollis and bisaccate pollen;the Valanginian-Hauterivian one by ferns(Cyatheaceae,Dicksoniaceae),Ginkgocycadophytus and bisaccate pollen;the Barremian one by ferns(Cyatheaceae,Dicksoniaceae);the Aptian one by ferns(Cyatheaceae,Dicksoniaceae,Gleicheniaceae) and Ginkgocycadophytus;and the Albian one by ferns(Schizaeaceae) and bisaccate pollen.In the Albian the floral diversity raises with the angiosperms appearing.  相似文献   
86.
The active role of fluids in the formation of ore-localizing structures expressed in dilatancy and hydraulic fracturing is suggested from the results of detailed comprehensive study of the Tokur gold deposit in the Upper Amur region, Russia, and the surveying of the published data on fluid pressure that characterizes formation of other hydrothermal deposits different in depth, morphology of orebodies, and their localization with respect to rocks of various permeability. Development conditions and possible implications of hydraulic fracturing for ore formation are considered. Indications of involvement of this mechanism in the orebody formation at the Pokrovsky, Berezovsky, and Nezhdaninsky gold deposits in Russia and the Bendigo deposit in Australia are discussed.  相似文献   
87.
Peter Lindner 《Geoforum》2007,38(3):494-504
Soviet collectives in general and especially the kolkhozes in rural areas were much more than merely production units. They regulated a significant part of everyday life in the villages and thus have to be seen as all-embracing social institutions, constituting the bedrock for rural communities. Relying on the homogenising effect of the kolkhoz-mechanism most authors who analyse the process of transformation in the Post-Soviet Russian countryside highlight the failures of privatisation and consequently presume continuity and not change. This paper argues, first, that in view of the weakness of the central state in the 90s a considerable leeway existed at the local level for different ways and degrees to implement the reform legislation and, second, that the concrete outcomes of the restructuring can only be adequately understood focusing on interests and power relations on the micro level rather than dealing with farms as such as the ‘acting units’.The common vantage point for most of the kolkhozes was an “alliance for the locale” between management and workers. It had its roots in the fear to become “slaves on one’s own land” if non-local investors would be allowed to buy agricultural land, to remain without infrastructure like streets, water supply and kindergartens if the kolkhoz would be divided up and to lack the machinery to work the private plots without the support of the farms. But beyond this consensus the chairmen of the collective farms could rely on a bulk of different allocative and authoritative resources to stage-manage privatisation. This introduced a highly ‘individual’ moment in the process and led to rising disparities and an increasing disintegration of rural Russia in the 1990s. Using a farm in southern Russia as an example the closer look at these resources and the “failed privatisation” unveils, that not continuity, but hybrid amalgamations of old and new characterise the Post-Soviet Russian countryside.  相似文献   
88.
A luminescence-based approach to the rapid characterisation of sites in terms of their datability and sedimentary history is described (luminescence profiling), and contrasting results presented for three Palaeolithic archaeological sites in Russia. Three mineral/grain-size fractions (polymineral silt-sized, polymineral sand-sized, quartz-enriched sand-sized) were separated from each of many small samples taken through the sites’ stratigraphies. Luminescence signals from the different fractions were measured using infra-red light, blue light, and thermal stimulation. Patterns in luminescence sensitivity and equivalent dose values are used to indicate which sites, samples, fractions and/or signals may yield meaningful luminescence ages, and the experimental effort that may be required to obtain said ages. Case studies range from a site where a detailed chronostratigraphy might be produced using a limited number of full luminescence dates to tie in the profiling results, to a site where profiling indicates there is little chance of producing useful luminescence dates. These interpretations are based on dialogue between the luminescence profiling results and archaeological, palaeoenvironmental, and geomorphological evidence. Luminescence profiling is shown to be a useful tool for understanding sedimentological process at each site, independent of full luminescence dating.  相似文献   
89.
While previous studies have focused on impacts of average climate change on Russian agriculture and water resources, this study takes into account the impact of changing frequency and spatial heterogeneity of extreme climate events, and the reliance of most of Russia on a few food producing regions. We analyze impacts of the IPCC A2 and B2 climate scenarios with the use of the Global Assessment of Security (GLASS) model (containing the Global Agro-Ecological Zones (GAEZ) crop production model and the Water-Global Assessment and Prognosis (WaterGAP 2) water resources model). As in previous studies we find that decreased crop production in some Russian regions can be compensated by increased production in others resulting in relatively small average changes. However, a different perspective on future risk to agriculture is gained by taking into account a change in frequency of extreme climate events. Under climate normal conditions it is estimated that “food production shortfalls” (a year in which potential production of the most important crops in a region is below 50% of its average climate normal production, taking into account production in food-exporting regions) occur roughly 1–3 years in each decade. This frequency will double in many of the main crop growing areas in the 2020s, and triple in the 2070s. The effects of these shortfalls are likely to propagate throughout Russia because of the higher likelihood of shortfalls occurring in many crop export regions in the same year, and because of the dependence of most Russian regions on food imports from a relatively few main crop growing regions. We estimate that approximately 50 million people currently live in regions that experience one or more shortfalls each decade. This number may grow to 82–139 million in the 2070s. The assessment of climate impacts on water resources indicates an increase in average water availability in Russia, but also a significantly increased frequency of high runoff events in much of central Russia, and more frequent low runoff events in the already dry crop growing regions in the South. These results suggest that the increasing frequency of extreme climate events will pose an increasing threat to the security of Russia's food system and water resources.  相似文献   
90.
Recent Russian legislative and policy documentation concerning national progress towards sustainable development has suggested that the attainment of such a state would represent the first stage in the development of the noosphere as outlined by the Russian scientist Vladimir Ivanovich Vernadsky (1863-1945). This paper explores Vernadsky’s model of evolutionary change through a focus on his work on the biosphere and noosphere in an attempt to further understanding of the way in which Russia is approaching the concept of sustainable development in the contemporary period. It is argued that the official Russian interpretation of the noosphere idea tends to obscure the evolutionary and materialist foundations of Vernadsky’s biosphere-noosphere conceptualisation. At the same time, the concluding section of the paper suggests that the scope of Vernadsky’s work can be used to stimulate the search for a more coherent approach to work in areas of sustainable development and sustainability across the span of the social and physical sciences.  相似文献   
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