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日本的滑坡研究及滑坡整治工程技术 总被引:4,自引:0,他引:4
本文中总结了作者赴日参加学术交流和现场考查期间所了解到的情况,较全面的介绍了日本在滑坡理论研究、防治工程技术、监测予报等方面所应用的理论、技术手段、仪器设备以及最新进展。作者最后以地附山滑坡为典型实例,说明日本在滑坡整治方面的研究成果及在防治工程中的成功应用。 相似文献
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以钻孔灌注桩周边与地层的有效结合,提高桩周摩阻力为目的,通过所施工的钻孔灌注桩基础工程实例,从钻进成孔工艺,缩短中间待灌时间,改善灌注方法等方面进行了综合分析,提出了一些具体作法和基本理论。所提出的基本作法,已在施工中得到应用,并取得了较好的效果。 相似文献
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芜湖青弋江滑坡的抗滑桩治理设计 总被引:1,自引:1,他引:1
本文以一个滑坡基本资料不够完善而采用抗湍桩为治理手段的坡体破坏作为研究对象,应用现场静力触探试验近似判断滑动位置,以传递系数法复滑坡土层抗剪强度,在有渗流的不利工况下考虑渗流力,采用悬臂桩法计算刚性抗滑桩。 相似文献
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陆面过程研究的现状与发展趋势 总被引:25,自引:4,他引:25
对目前陆面过程研究的现状及存在的问题进行了总结,并且提出了与边界层研究有关的几个前沿方向:①非均匀下垫面地表湍流通量的参数化及中尺度通量的参数化方法;②边界层理论在复杂地形条件下的应用,以及次网格地形对通量输送的影响;③进一步改进GCM中冠层地表水文参数化;④边界层的层云和层积云的参数化。 相似文献
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混沌理论及其在地学中的应用前景 总被引:1,自引:0,他引:1
混沌理论作为一种普适性很强的新理论,在地球科学中的应用日前广泛,其意义已渐为人们所认识和关注。本文介绍了混沌在地球中的部分应用,认为混沌理论开阔了人们研究地学中复杂问题的思路;同时,地学中一些重大问题的解决也必将丰富和混沌理论。 相似文献
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“~(210)Po法”是近几年来引进的一种探测 a 粒子的铀矿普查的放射性方法。现在已有不少单位把这种方法也应用到地热区的勘探中,并取得了一定的效果。一九八三年我们与浙江水文地质队一起应用这种方法对浙江西部的湍口地热区进行工作,从所测出的结果经过分析整理后可以看出,这一方法对搞清地热区的构造情况可以起到一定作用。 相似文献
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大孔径闪烁仪研究区域地表通量的进展 总被引:15,自引:0,他引:15
地表湍流通量包括感热通量和潜热通量的准确测定对天气气候、农业、水文和水资源管理等意义重大。在几公里到几十公里尺度上有代表性的区域湍流通量的观测研究,特别在非均匀下垫面情况下,仍然非常困难。近年来蓬勃发展的大孔径闪烁仪(LAS)为这一问题的解决提供了全新手段。在介绍大孔径闪烁仪原理的基础上,综述了国内外利用大孔径闪烁仪开展区域地表通量观测研究的进展,包括在不同地表的LAS测量与涡动相关方法有关结果的对比,影响测量精度的关键因子分析,以及在区域地表通量遥感估算模型检验中的应用等,最后对大孔径闪烁仪的应用前景进行了展望。 相似文献
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Ice-flow patterns and dispersal of erratics at the southwestern margin of the last Scandinavian Ice Sheet: signature of palaeo-ice streams 总被引:1,自引:0,他引:1
KURT H. KJæR MICHAEL HOUMARK-NIELSEN NIELS RICHARDT 《Boreas: An International Journal of Quaternary Research》2003,32(1):130-148
An extensive set of proxy-data was acquired from eastern and central Denmark in order to study the dynamic behaviour of the southwestern margin of the last Scandinavian Ice Sheet. We examine the last three glacier advances of the Late Weichselian: the Main advance from central Sweden, representing the maximum ice extent at this time ( c. 21–20 ka BP), and the two succeeding Baltic advances ( c. 18–15 ka BP). Directional properties from tills and glaciotectonic overprints are used to reveal large-scale flowline patterns. Together with the geomorphological outline of ice margins, flowlines were successively more fan-shaped, indicating that the dependence of the subglacial topography increases as ice advances become younger. It is suggested that while the ice thickness decreases, more lobate configurations of ice margins are created as a result. Clast-compositional data derived from the fine-gravel fraction in tills are used to reconstruct dispersal patterns of erratic material. The dispersal patterns during the three advances show a gradually diminishing influence of local Pre-Quaternary bedrocks and older glacial deposits, and progressively longer transport distances of far-travelled erratics. We speculate that the principal factor governing this development is a successively decreasing interaction between the ice and its bed, which influences the concentration of erratics, debris comminution processes and the basal ice velocity. We envisage the Main advance from central Sweden as a slow-flowing inter-stream ice body with high bed interaction compared to the succeeding Baltic advances, which we regard to have been rapid flowing ice streams with limited bed interaction. 相似文献
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断裂构造研究进展对工程地质学的启示 总被引:4,自引:0,他引:4
在长期地质作用下形成的岩体和岩体结构是工程地质学研究的基本内容,它们的形成和演化主要受控于构造作用,而系统地解析体所经历的构造作用是认知岩体结构,抽象和概括岩体工程地质模型的突破口,因此,重视和应用现代构造地质学研究的新理论,新方法必将会对岩体工程地质学研究起着重要的指导意义。本文系统总结了与工程地质研究相关的现代构造地质学理论和思维观的研究进展,在此基础上分析了这些理论方法对工程地质工作的启示和指导意义,希望起到抛砖引玉的作用。 相似文献
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The timing and extent of latest Pleistocene and Holocene alpine glacier fluctuations in the Himalaya and Tibet are poorly defined due to the logistical and political inaccessibility of the region, and the general lack of modern studies of the glacial successions. Nevertheless, renewed interest in the region and the aid of newly developing numerical dating techniques have provided new insights into the nature of latest Pleistocene and Holocene glacier oscillations. These studies provide abundant evidence for significant glacial advances throughout the Last Glacial cycle. In most high Himalayan and Tibetan regions glaciers reached their maximum extent early in the Last Glacial cycle. However, true Last Glacial Maximum glacier advances were significantly less extensive. Notable glacier advances occurred during the Lateglacial and the early Holocene, with minor advances in some regions during the mid-Holocene. There is abundant evidence for multiple glacial advances throughout the latter part of the Holocene, although these are generally very poorly defined, and were less extensive than the early Holocene glacier advances. The poor chronological control on latest Pleistocene and Holocene glacial successions makes it difficult to construct correlations across the region, and with other glaciated regions in the world, which in turn makes it hard to assess the relative importance of the different climatic mechanisms that force glaciation in this region. The Lateglacial and Holocene glacial record, however, is particularly well preserved in several regions, notably in Muztag Ata and Kongur, and the Khumbu Himal. These successions have the potential to be examined in detail using newly developing numerical dating methods to derive a high-resolution record of glaciation to help in paleoclimatic reconstruction and understanding the dynamics of climate and glaciation in the Himalaya and Tibet. 相似文献
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Holocene glacial advances in the Banff-Jasper-Yoho area of the Canadian Rocky Mountains have been extremely limited in extent. Limiting 14C dates from two sites within 1 km of contemporary glaciers of fresh terminal moraines indicate that the late Wisconsin Ice Sheet and valley glaciers disappeared prior to 9660 yr B.P. Two subsequent glacial advances are recognized. The earlier Crowfoot Advance is represented by moraines and rock-glacier deposits overlain by Mazama ash (6600 yr B.P.) and is therefore early Holocene or possibly late Wisconsin in age. The late Neoglacial Cavell Advance of the last few centuries is dated by dendrochronology and lichenometry. In addition, there is fragmentary, undated evidence of intermediate-age advance(s), mainly from rock-glacier deposits. All these advances were of limited extent (1–2 km beyond present ice margins) and the Cavell Advance was usually the most extensive. Major exceptions to this pattern occur only where rock glaciers or extensive ice-cored moraines developed during the earlier advance(s?). These deposits were not overrun by glaciers during the Cavell Advance because of their relatively greater downvalley extent and the physical barrier they presented to subsequent glacial advances. Earlier work which postulated more extensive early Holocene advances in the Canadian Rocky Mountains is shown to have inadequate dating control: Many of the features previously attributed to older Holocene events are late Wisconsin in age. 相似文献
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湖相碳酸盐岩生油岩研究进展 总被引:7,自引:0,他引:7
综述了湖相碳酸盐岩生油岩研究的新进展,其主要表现在以下几个方面:(1)形成环境;(2)组成特征;(3)有机质含量 ;(4)有机地化特征;(5)热演化特征;(6)二次成烃问题。指出湖相碳酸盐岩生油岩的研究具有重要的理论生实践意义。 相似文献
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An updated classification scheme for mantle-derived garnet, for use by diamond explorers 总被引:1,自引:0,他引:1
Mantle-derived garnets recovered in diamond exploration programs show compositional variations in Cr, Ca, Mg, Fe and Ti that reflect the chemical, physical and lithological environments in which they occur, occasionally together with diamond. The association of diamond with mantle garnet has progressed through a number of geochemical advances, most notably those of Dawson and Stephens (1975) and Gurney (1984), which are integrated in this work with less well known petrological advances made primarily in xenolith and experimental petrology. A simple, robust garnet classification scheme is formulated which accommodates empirical garnet–diamond relationships for peridotitic (G10, G9, G12), megacrystic (G1), Ti-metasomatised (G11), pyroxenitic (G4, G5) and eclogitic (G3) lithologies in eight distinct garnet classes. The calcium-saturation characteristics of harzburgitic (G10), lherzolitic (G9) and wehrlitic (G12) garnets are described by a Ca-intercept projection that also shows promise as a relative barometer for garnet lherzolite (Grütter and Winter, 1997). Thermobarometric aspects of garnet–diamond associations are highlighted in the scheme through the use of the minor elements Mn and Na, though analysis by anything other than an electron microprobe is not required for classification. A “D” suffix is added to the G10, G4, G5 or G3 categories to indicate a strong compositional and pressure–temperature association with diamond. The scheme remains open to improvement, particularly with regard to delineation of pyroxenitic (or websteritic) diamond associations and to advances in Ca-in-garnet and Na-in-garnet thermobarometry. 相似文献
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Janet M. Hergt Ricardo Arevalo Jr L. Paul Bèdard Jeremy Bellucci Jacinta Enzweiler Klaus Peter Jochum Kathryn L. Linge William F. McDonough Regina Mertz-Kraus Michael Wiedenbeck Xiaohong Wang Jon D. Woodhead 《Geostandards and Geoanalytical Research》2010,34(4):325-326
This collection of articles represents the fourth in a series of reviews in which authors have aimed at capturing the key advances in a range of analytical fields ( Hergt et al. 2005, 2006, 2008 ). The publication period under review is 2008–2009 and the intention here is to provide readers with a summary of the most influential developments published during this period, across a broad range of topics appropriate to the Earth and environmental sciences. Most authors comment on the ways in which the emphases of research in their specific fields of examination have changed over time. All note an increase in rigour and focus on data quality. Whether advances have taken place in instrumentation, sample manipulation or data deconvolution, there are a large number of dedicated scientists out there contributing to the high quality of geochemical data employed in geological and environmental research. 相似文献