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WILLIAM A. S. SARJEANT 《Geology Today》1994,10(6):228-231
In the early years - the so called 'Golden Age' - of mystery fiction, there were a number of towering figures - the 'great detectives'. However, only two of them included geology among their concerns. Their abilities and achievements are here compared and assessed. 相似文献
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The Golden Pride gold deposit (∼3 Moz) is located in the central part of the Nzega Greenstone Belt at the southern margin
of the Lake Victoria Goldfields in Tanzania. It represents an inferred Late Archaean, orogenic gold deposit and is hosted
in intensely deformed meta-sedimentary rocks in the hanging wall of the approximately E–W striking Golden Pride Shear Zone.
The hanging-wall sequence also includes felsic (quartz porphyritic) to mafic (lamprophyric) intrusions, as well as banded
iron formations. Hydrothermal alteration phases associated with mineralisation are dominated by sericite and chlorite. Two
main ore types can be distinguished, chlorite and silica ore, both occupying dilational sites and structural intersections
in the hanging wall of the main shear zone. Sulphide minerals in both ore types include pyrrhotite, arsenopyrite, pyrite and
accessory sphalerite, galena, sulphosalts and Ni–Co–Bi sulphides. Gold and tellurides are late in the paragenetic sequence
and associated with a secondary phase of pyrrhotite deposition. Sulphur isotope compositions range from −6 to 7 per mil and
are interpreted to reflect contributions from two distinct sources to the mineralising fluids in the Golden Pride gold deposit.
A redox change, potentially induced by the intrusion of mafic melts, together with structural elements in the hanging wall
of the Golden Pride Shear Zone, are interpreted to be the main controls on gold mineralisation in this deposit. 相似文献
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Uncertainty is ubiquitous in geology, and efforts to characterise and communicate it are becoming increasingly important. Recent studies have quantified differences between perturbed geological models to gain insight into uncertainty. We build on this approach by quantifying differences in topology, a property that describes geological relationships in a model, introducing the concept of topological uncertainty. Data defining implicit geological models were perturbed to simulate data uncertainties, and the amount of topological variation in the resulting model suite measured to provide probabilistic assessments of specific topological hypotheses, sources of topological uncertainty and the classification of possible model realisations based on their topology. Overall, topology was found to be highly sensitive to small variations in model construction parameters in realistic models, with almost all of the several thousand realisations defining distinct topologies. In particular, uncertainty related to faults and unconformities was found to have profound topological implications. Finally, possible uses of topology as a geodiversity metric and validation filter are discussed, and methods of incorporating topological uncertainty into physical models are suggested. 相似文献
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Fact and fiction: Geography and literature 总被引:1,自引:0,他引:1
Main epistemological reflections in Geography developed since the 1970s emphasize holistic perspectives in which intuition has an important cognitive. Bringing forward the ideas lifeworld and espace véçu important currents in this approach put in relief the sense of place, the affective ties with the environment, the aesthetic and landscape symbology, the genius loci and the spatial-temporal rythms connected to personal experiences. In this context, literary works (tales, novels, or short stories) are important because they provide authentic and indespensable testimony of the influence of human experience on place.The analysis of the vast bibliography on geographic interpretation of literary sources reveals typologies: studies on the links between real and literary landscapes, understanding of the sense of place, the concepts of rooting and uprooting, the definitions of inscapes and territorial consciousness. These five thematic foci allow the interpretation of the relationship existing between geography — regarded as landscape and place — and literary works —considered as the expression to define and fix the culture and feelings of a human group with respect to its own space and place. 相似文献
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V. T. Trofimov 《Moscow University Geology Bulletin》2008,63(2):59-69
The contents and relationships of environmental geology, ecological geology, and geoecology are discussed. It is shown that they differ in their subjects, directions and objects of investigation, as well as their scientific and practical tasks. Hence, these concepts and the spheres of knowledge they determine can be neither identified with nor substituted for each other because this inevitably causes terminological confusion and hampers the development of ecological problems, and not only in geology. Environmental geology, by its content, is a collection of data obtained by traditional geological sciences and has no specially developed conceptual base. It is an anthropocentrically oriented field of geological knowledge, unlike ecological geology, which is oriented biocentrically and has a wider volume. Geoecology is an interdisciplinary science studying the effect of all abiotic spheres of living matter. Ecologically oriented geological sciences are intended to provide information on only one of these spheres—the lithosphere. 相似文献
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华北克拉通对前寒武纪超大陆旋回的基本制约 总被引:33,自引:4,他引:33
全球大陆克拉通在前寒武纪至少记录了3次超大陆聚合-裂解的构造旋回。不同大陆前寒武纪地质的研究证明,板块的构造模式可以前推至新太古代。超大陆的聚合表现为大规模造山带的穿时性发育,而裂解则表现为大陆裂谷系、非造山花岗岩及巨型基性岩浆岩省的同期快速发育。广泛的区域地质研究揭示华北克拉通前寒武纪地质构造演化具有明显的阶段性差异特征,克拉通主体形成于新太古代陆壳增生与碰撞造山过程。华北克拉通在太古宙末期首次经历强烈的裂解作用,在古元古代晚期涉及强烈的陆缘再造作用。在古元古代末期发生第二次大规模的裂解活动,随后以中元古代末期的造山带拼合为Rodinia超大陆的组成部分。详细的区域构造对比证明,华北克拉通长期以来与波罗的地质、东南极克拉通、印度南部克拉通、巴西克拉通等具有构造亲缘关系。 相似文献
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Earthquake geology: Methods and applications 总被引:1,自引:0,他引:1
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环境地质研究进展与展望 总被引:2,自引:0,他引:2
环境地质学与其他地质学科的最大区别是,把人类活动作为一种地质作用营力加以研究,这是前所未有的。面向国民经济、国家重大工程建设和城市化的快速兴起与发展,环境地质学科得到了迅速发展。关注气候变化、海岸带发展、城市化、地下水资源与地质环境的相互关系至关重要。要重视地质灾害形成发育的规律,特别是人类工程活动与自然地质作用相互关系的研究。地质灾害防治和群测群防,在今后一个相当长的时期内仍然是研究重点。持久地为社会、为公众、为政府服务,提高地质科学在环境保护中的作用与地位,提高公众对环境地质学的认知与认同,才能采取共同行动,为可持续发展做出贡献。 相似文献
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环境地质学的发展与挑战 总被引:3,自引:1,他引:3
人类只有一个地球,奋起拯救地球和地球上包括人类自己在内的生物———对环境和环境保护意识的觉醒,是人类20世纪对可持续发展的一个伟大贡献。其中,地质科学对人类可持续发展理念的形成功不可没。地质科学是研究地球系统的科学,历来与人类社会的生存和发展密切联系在一起。传统的地质科学注重研究地球的形成及其演化历史,在满足不断前进的社会经济发展对矿产资源需求的同时,自身也得到了发展。地质学家弄清楚了地球已经有45亿年的历史;认识到地球是一个动态的、完整的系统。地质科学在研究地球演化历史时,总要研究生物的进化过… 相似文献
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Kettle holes - stratigraphical archives for Weichselian geology and palaeoenvironment in northernmost Sweden 总被引:1,自引:1,他引:1
ROBERT LAGERBÄCK ANN-MARIE ROBERTSSON 《Boreas: An International Journal of Quaternary Research》1988,17(4):439-468
An active search for pre-Holocene organic deposits in stratigraphically well-defined positions has proved to be a useful tool for reconstruction of glacial and non-glacial Weichselian development in northernmost Sweden. The investigations have been concentrated to kettle holes connected to eskers belonging to a morphologically prominent northwesterly glacial system characterized by extensive drumlinization. Organic deposits, radiocarbon-dated as older than the Holocene, have been found at some 25 localities. Some sites display two organic-bearing sequences separated by a till bed. The pollen flora in the lowest organic bed reflects an interstadial vegetational development: Arctic shrub and herb tundra-subarctic light birch forestherb tundra with ericaceous shrubs and dwarf birch. This interstadial is correlated with Peräpohjola in Finland. During the younger Tärendö Interstadial the vegetational development was similar, but a more continental climate is indicated hy high values of steppe plants, e.g. Artemisia and Chenopodiaceae. The Tärendö Interstadial, correlated with Odderade, wascharacterized by open, unstable soils due to periglacial processes such as cryoturbation and eolian activities. The Weichselian glaciation is divided into three glacial stades separated by ice-free interstadials in the area studied. Except for a zone with S-SW drumlinization the impact of the two later ice sheets is insignificant. 相似文献
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JANE DOVE 《Geology Today》1992,8(5):176-179
Cathedrals are geologically fascinating and that of Exeter is no exception. Outward appearances are deceptive; although the outer medieval walls are made of Greensand, the core is made of local Permian breccia and volcanics. Beer Stone is used less extensively than generally supposed, although it is important for carving. Nineteenth-century improvements in transport encouraged greater use of Cotswold and East Midland oolites for the cathedral repairs. Over time, these and local stones have weathered differentially, which has encouraged masons to return to Greensand for very recent repairs. 相似文献
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环境地质学进展与展望 总被引:3,自引:0,他引:3
哈承佑 《水文地质工程地质》1999,(5)
环境地质学是随着人类活动和地质环境之间相互作用的不断加深而形成和发展的。自50年代起,我国开展了大量的环境地质工作,未来环境地质学有着广阔的研究领域。环境地质学研究是可持续发展战略的一部分 相似文献
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一、现行养老保险制度的基本政策 1995年3月,根据党的十四届三中全会作出的《关于建立社会主义市场经济体制若干问题的决定》精神,国务院出台了《关于深化企业职工基本养老保险制度的通知》,即国发[1995]6号文件。由于6号文件提出了 相似文献
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《China Geology》2018,1(1):137-157
The development of metamorphic petrology to metamorphic geology in China has a long history. Ancient basement metamorphic rocks are distributed primarily in the North China Craton, the Yangtze Block and Tarim Craton. They are mainly made up of plutonic gneiss and metamorphosed supercrust rock, transformed to granulite facies through Archean Paleoproterozoic. Many of the Paleoproterozoic metamorphic rocks have undergone high-pressure granulite facies metamorphism with a clockwise metamorphic evolution path. The ultrahigh temperature (UHT) granulites from the Late Paleoproterozoic are found in North China Craton. Many high-precision chronological data have allowed preliminary construction of the formation and evolutionary framework of different metamorphic basements. Primarily there are low-temperature and high-pressure blue schist, high-temperature and high-pressure granulite and ultrahigh-pressure (UHP) eclogite facies metamorphic rocks in the Phanerozoic orogenic belt. The discovery of eclogite in the Sulu orogen and a large quantity of coesite in its country rocks show that there was a deep subduction of voluminous continental materials during the collision process between the Yangtze block and the North China Craton in the Early Mesozoic phase. From the studies of, for instance, organic matter vitrinite reflectance, illite crystallinity, illite (muscovite) polytype and illite (muscovite) b dimension, the Late Paleozoic strata in the eastern region of Inner Mongolia and the north-central region of NE China have only experienced diagenesis to an extremely low-grade metamorphism. The discovery of impact-metamorphosed rocks in Xiuyan area of Liaoning province has enriched the type and category of metamorphic rocks in China. The phase equilibrium method has been widely used in the study of metamorphism of middle and high-grade metamorphic rocks. On the basis of existing geologic surveys and monographic study results, different scholars have respectively compiled 1:1500000 Metamorphic Geological Map and Specifications of Qinghai Tibet Plateau and its Adjacent Areas, 1:2500000 Metamorphic Tectonic Map of China, and the 1:5000000 Metamorphic Geological Map and Specifications of China, among others repectively, which have systematically summarized the research results of metamorphic petrology and metamorphic geology in China. 相似文献