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1.
A. S. Issar 《Environmental Geology》1993,21(3):152-159
Limestone and dolostone aquifers play a major role in the water supply system of Israel. In many cases, there are brackish to saline springs at their outlets. The source of the saline water and the mechanism of salinization differ from place to place. In some cases, it is due to mixing with seawater (Mediterranean or Dead Sea) at the fresh-saline water interface, while in other cases deepseated brines emerge along regional faults. The general policy for reclaiming the fresh component of the water before mixing with the saline component is to try to catch the fresh water as far as possible upstream from the outlet. In most cases, this is the area where the mixing takes place. The main case histories in Israel are discussed in this paper. 相似文献
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我国深部找矿研究进展综述 总被引：18，自引：4，他引：14
进入21世纪以来,深部矿已成为我国矿产勘查的重要对象,从而标志着矿产勘查进入了一个新的阶段.由于深部矿相对浅部矿具有埋深大、矿化信息弱、综合地质研究程度低的特点,使传统成矿理论的指导作用和勘查技术方法应用的有效性受到较大的影响,造成深部矿勘查的难度加大.为了减少深部矿勘查的盲目性和风险性,人们重视和加强了深部找矿地质成矿理论和技术方法的研究,并取得了一定的进展.研究资料表明,成矿系统、第二矿化富集带、矿床成矿深度厘定、矿床深部成矿特征、矿田深部构造以及深部找矿前景的定量评价等研究内容已成为当前我国深部找矿工作中地质成矿理论研究的热点,大深度物探技术和深穿透的化探新方法、高分辨率航卫遥感技术以及大深度的钻探技术等方法的研制和应用已成为深部找矿技术的发展方向. 相似文献
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In landscape diagnosis landscapes are evaluated on the basis of their natural and technological characteristics with regard to the possibilities and risks of intensive utilization. Land use is an essential criterion for the evaluation of the condition of landscapes. Remote sensing will allow for an analysis of large areas with regard to land use. Landscape diagnosis through satellite photographs will be illustrated in two examples. In the first one multitemporal evaluation of satellite photographs is discussed with particular reference to attempts made to characterize the utilization of landscape potentials. In the second example attempts have been made to classify medium-sized landscape units by satellite photographs, with additional characterization through thematic maps based on the Atlas GDR. 相似文献
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Greta M. Eskenazy 《Geochimica et cosmochimica acta》1980,44(7):1023-1027
The content and distribution of In in 168 samples from 7 coal deposits in Bulgaria were studied, using a spectrochemical method with a detection limit of 0.002 ppm. Indium is present in all samples, its content varying from 0.002 to 0.167 ppm in the coal and from 0.005 to 0.57 ppm in the ash. The mean contents for individual deposits do not differ statistically, and for all the deposits the In concentration (ppm) can be expressed generally by the equation In = 0.00068 A (A is the coal ash content in %).Of the petrographic constituents of coal, vitrain, xylene and liptain are enriched in In. In is associated with both the organic and with the inorganic matter of the coal. Inorganic matter and clay minerals in particular, act only as carriers of Indium. In contrast, organic matter concentrates In only to a small degree relative to other trace elements. 相似文献
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虽然中国城市地下空间的建设规模和速度已经位居世界首位,但中国城市地下空间的开发利用仍存在着一系列亟须解决的问题和挑战。文章通过调研不同城市的地下空间开发利用现状并借鉴其他国家的经验,从管理、技术、运维和人才4个层次解析了中国城市地下空间开发利用所面临的问题和挑战。具体地说,在管理方面,缺少管理依据,缺失综合管理机构,管理机制和管理制度仍不健全,亟须建立中国特色的地下空间管理体系;在技术方面,复杂地质、复杂环境下的扰动施工控制技术仍需进一步提高,缺少新型的装备和技术,深层地下空间的开发利用尚处于起步阶段,亟须建立基于开发与保护的全深度、全资源开发利用技术体系;在运维方面,缺少地下基础设施维护与更新的成套技术体系,缺乏对运维信息的管理和应用,灾害下的地下空间逃生救援体制不完善,亟须建立数字化、智慧化的安全运维体系;在人才方面,尚未建立完善的地下空间学科体系,缺乏跨学科、复合型人才,亟须建立健全的地下空间人才培育体系。 相似文献
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A study of the fluoride concentration in several marine areas around Sweden is reported. It has been established that the fluoride-chlorinity relationship at low chlorinities is much affected by river runoff due to removal of fluoride by the agency of settling particles. The effect of this is enhanced where rivers open into relatively high-saline water. In the Baltic, which is strongly influenced by river runoff, the fluorido to chlorinity ratio is much higher than in the open oceans. In the oxygenated layers of the Baltic fluoride shows little variation with time, but in the anoxic layers the fluoride concentration decreases with time. In the deeper layers of the Kattegatt an increase in fluoride could be noted which might be due to dissolution of minerals. An overall relationship between fluoride concentration and chlorinity in offshore waters has been established. 相似文献
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某矿区主要以辉钼矿为主,同时伴生有黄铁矿和少许铅锌矿。该矿区地层复杂,断层较多,主要施工难点是粉碎型破碎带和含断层泥与角砾的断层带。针对该复杂地层,选择合适的钻进施工工艺,能够有效的减少事故率和提高钻进效率。 相似文献
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南秦岭金矿成矿的几点认识于学元，郑作平（中国科学院广州地球化学研究所，广州５１０６４０）关键词金矿床，成矿带，南秦岭秦岭地质构造极其复杂，是一个巨大的缔向构造带，也是我国重要的有色金属矿产基地。近几年来，随着对秦岭地区地质研究强度的加强，在贵重金属找... 相似文献
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Nano Ruzin 《GeoJournal》2000,52(2):353-357
The authority of Marshall Tito and his newly crafted iconography of `brotherhood and unity' temporarily marginalized the ethnic deographies of the peoples in the Yugoslav Federation. In the 1990s this Yugoslavia was run over by time. The Republic of Macedonia was among the newly emerging states. In Macedonia the multi-ethnic mosaic was complicated by the confusion of old and new iconographic impulses. In 2001 the Macedonian crisis developed as a result of the spread of the new regional Albanian identity spread by the domino effect to the areas with mixed population in the Balkans after the events in Kosovo. Differences between Macedonians and Albanians are analyzed in terms of family structure, religion and ethnic and national affiliation. The politics based on these cleavages and their ensuing, contested iconographies are set out. 相似文献
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Nano Ruzin 《GeoJournal》2001,52(4):353-357
The authority of Marshall Tito and his newly crafted iconography of `brotherhood and unity' temporarily marginalized the ethnic deographies of the peoples in the Yugoslav Federation. In the 1990s this Yugoslavia was run over by time. The Republic of Macedonia was among the newly emerging states. In Macedonia the multi-ethnic mosaic was complicated by the confusion of old and new iconographic impulses. In 2001 the Macedonian crisis developed as a result of the spread of the new regional Albanian identity spread by the domino effect to the areas with mixed population in the Balkans after the events in Kosovo. Differences between Macedonians and Albanians are analyzed in terms of family structure, religion and ethnic and national affiliation. The politics based on these cleavages and their ensuing, contested iconographies are set out. 相似文献
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我国登陆台风影响区地质灾害易发性分析 总被引：2，自引：0，他引：2
地质环境脆弱的地区,台风的特大暴雨可以诱发山体滑坡和泥石流等地质灾害,造成严重人员伤亡。本文分析了我国登陆台风影响区域内的地质灾害时空分布特点,利用信息量方法,通过灾害的易发性区划来分析登陆台风影响区地质灾害特征,进而比较台风和非台风影响条件下地质灾害产生的地理条件和信息量差异。分析结果表明,在台风强降雨条件下,地质灾害的触发地质环境条件较非台风降雨触发地质灾害明显降低,地质灾害脆弱性明显增加。 相似文献
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In this paper we have attempted to pose a methodological problem, and to provide answers to some fundamental measurement problems in research. In the search for the regularities which are thought to underlie the phenomena we study, geographers and others have often had recourse to Graph Theory to represent certain situations. Once some pattern of interaction can be depicted by using a group of points (nodes) joined by lines (links or edges), interest is often centered around the degree of correpondence between two graph-theoretic representations of empirical evidence. We have suggested methods for answering the question: are the link patterns for the two graphs so similar that they could not reasonably have arisen by chance? The approach to the solutions are based on probability theory and the properties of certain statistical distributions — the binomial, the hypergeometric, the hypergeometric?onominal and other combinations. In each case we have provided a rationale for the suggested solution as well as tables and computational procedures. The examples have been chosen from a wide variety of situations, for graph-theoretic representations are found in many fields of investigation. 相似文献
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华南地区石炭纪-早二叠世早期成冰期的地球生物学过程与烃源岩的形成 总被引：1，自引：0，他引：1
石炭纪-二叠纪冈瓦纳大陆成冰事件控制着全球(尤其是华南地区) 的海平面变化, 从而决定着生境型及生产力的变化.冈瓦纳大陆成冰事件造成石炭纪-早二叠世早期有4次全球性海退, 其中Tournasian末期到Visean早期的海退在华南地区最为明显, 导致生境型发生了明显的变化.在盆地相区, 由斜坡相(Ⅴ1) 转变为下部浅海上部(Ⅳ1).在远岸碳酸盐台地区, 由上部浅海(Ⅲ1)、(Ⅲ2) 转变为潮间带(Ⅱ1)、潮下带(Ⅱ2).在连岸碳酸盐台地区, 由浅水碳酸盐沉积区(Ⅱ1)、(Ⅱ2) 转变为陆相或海陆交互相沉积区.通过对生境型、生物类群的分布及氧化还原环境的分析, 探讨了冰期与间冰期生物群的演替、海洋生物生产力及埋葬条件的变化, 进而确定成冰事件对烃源岩形成和分布的控制作用. 相似文献
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以伊敏煤田某露天煤矿横波地震勘探为例,介绍了制做适合野外施工的低噪声、大能量、且易于操作的横波震源的方法,并将各种特性的横波震源在不同介质中进行激发效果试验。根据试验结果确定了震源类型及数据采集参数,其中横波震源为12齿、重150kg、尺寸为110cm×90cm×20cm的爬钉型震板,在加载500kg的重物时耦合效果较好。横波资料的处理基本上与纵波处理的方法相同,由于该区反射波信噪比较高,区内地形平坦,静校正问题较易解决。在资料解释中利用反射波同相轴的形态,在时间剖面上圈定了断层、煤层冲刷带及煤层尖灭点的位置。另外应用速度谱资料求取的平均速度预测了该露天煤矿15、16煤的底板深度。 相似文献
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Shen Baofeng Peng Xiaoliang Luo Hui Mao DebaoTianjin Institute of Geology Ministry of Geology Mineral Resources Tianjin 《《地质学报》英文版》1994,68(1):15-29
Chinese Achaean greenstone belts are mainly distributed along the northern and southwestern margins of the North China platform. In terms of their geological characteristics, the greenstone belts in China are comparable to those in other countries but at the same time have unique features of their own. In view of their geochemistry, the Chinese greenstone belts may be grouped into three types: the Jiapigou type, Qingyuan type and Xiaoqinling type. The greenstone belts were formed possibly in a rift-type palaeo-tectonic setting, similar to that of the modern island are-continental margin mobile belts. 相似文献
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In Zimbabwe four contrasting gully locations and associated gully patterns are present, reflecting spatial variations in precipitation, bedrock, soil type and landuse. Deep dendritic gullies, associated with landslip activity and subsurface piping, characterise the wet Eastern Highlands and areas with sodic soils. Shallow discontinuous gully systems characterise bornhardt terrain in the Communal Lands. Dambo gullies tend to form a continuation of the fluvial system. The pattern and temporal variation of gullies was studied in three areas of Communal Land (Mhondoro-Ngesi, Mangewende, Mutema) with particular reference to the influence of average slope and landuse on gully development. In areas of sodic soils the gullies appear to be largely the product of natural processes and their development has only partly been influenced by landuse changes. In contrast the shallow gullies developed on granitic/gneissic terrain tend to occur on cultivated or recently cultivated land. The case studies indicate that a full assessment of gully development can only be achieved if a temporal perspective is also considered. 相似文献
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A. S. Alekseev G. A. Golodkovskaya L. L. Panasian 《Moscow University Geology Bulletin》2012,67(2):103-114
A new approach to the study of carbonate rocks that takes stratigraphic sequences, cycles, and lithotypes into account is proposed. The main features of the geological structure of the model site in the territory of Moscow in accordance with the stratigraphic scheme are considered. In the considered section, the cyclicity in carbonate rocks is noted. In addition, the physical and mechanical properties of limestone and dolomite samples from the Neverovo and Shchurovo cyclites were studied on the basis of R. Dunham??s classification of carbonate rocks (1962). It was proven that the physical and mechanical rock properties are connected with rock lithotypes, which describe their inner structural morphology. In this case, regular changes in rock properties with depth are not noted, which can be associated with the position of the samples within the sequence. According to the results we obtained, the conclusion was made that it is necessary to compile an atlas-inventory of Carboniferous rocks for the territory of Moscow. For this purpose, the main key points for the implementation of this project are proposed. 相似文献