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71.
This paper presents the results of engineering geological investigations and tunnel support design studies, carried out at the Sulakyurt dam site, northeast of Ankara, Turkey. The Sulakyurt dam will be used for flow control and water storage for irrigation projects. Studies were carried out both in the field and the laboratory. Field studies include engineering geological mapping, intensive discontinuity surveying, core drilling and sampling for laboratory testing. The diversion tunnel will be driven in rock mass, consisting of granite and diorite. Empirical, analytical and numerical methods were combined for safe tunnel design. Rock mass rating (RMR), Rock mass quality (Q) and Geological strength index (GSI) systems were used for empirical rock mass quality determination, site characterization and support design. The convergence–confinement method was used as analytical method and software called Phase2, a 2D finite element program, was utilized as numerical method. According to the results acquired from the empirical, analytical and numerical methods, tunnel stability problems were expected in both granite and diorite rock masses. The support system, suggested by empirical methods, was applied and the performance of suggested support system was evaluated by means of numerical modelling. It was concluded that the suggested support systems were adequate, since after applying the suggested support system to granite and diorite, tunnel deformation and the yielded elements around the tunnel decreased significantly. Thus, it is suggested that for more reliable support design empirical, numerical and analytical methods should be combined.  相似文献   
72.
在分析研究小型地质车载钻机的形式、功能与特点的基础上,提出了钻机车载化的新思路。根据地质调查工作现状,结合国内现有小型地质取样钻机,研制了CQK-50型全液压多功能车载取样钻机,并在野外物化探遥感异常验证钻探中取得了良好效果。  相似文献   
73.
张永勤 《探矿工程》2006,33(8):45-50
概述了我国地质找矿钻探市场现状及前景,分析研究了地质取样钻探传统的立轴钻机及全液压动力头钻机的优缺点及综合效能,针对国家提出加强地质工作的形势及中国的实际状况,提出了完善和改进我国现有钻探设备、提高我国地质找矿取样钻探效率、降低能耗及成本的观点及建议。  相似文献   
74.
基于对国内地质工程机械的研发现状的考虑,根据虚拟样机技术的特点,讨论了在地质工程机械领域实施虚拟样机技术的必要件,并提出了建立地质工程机械虚拟样机的策略。联合PRO/E、ANSYS及ADAMS建立了气动潜孔锤的虚拟样机模型,对气动潜孔锤虚拟样机进行了仿真,阐明了虚拟样机技术在地质工程机械领域的应用前景。  相似文献   
75.
本溪地质遗迹与地质公园的开发建设   总被引:1,自引:0,他引:1  
本文比较详细的说明了本溪地区存在的地质遗迹,并进一步论述了本溪地质遗迹的特征及保护现状,提出了开发建设本溪地质公园的设想,这对本溪地区旅游资源的保护及旅游业的发展有着十分重要的意义。  相似文献   
76.
77.
This study investigates the extent to which people's views on the causes and preventability of earthquake damage might be influenced by their degree of exposure to hazard as well as what information they have been given about the hazard. The results show that the provision of hazard zoning information influences judgements on preventability and causes of damage, but this effect depends on the degree of hazard faced by residents. In low hazard zones, information leads to the view that causes are manageable, whereas in high hazard zones information may induce a degree of fatalism. The use of public information in risk management needs to take into account the degree of risk faced by the recipients.  相似文献   
78.
The Ernest Henry Cu–Au deposit was formed within a zoned, post-peak metamorphic hydrothermal system that overprinted metamorphosed dacite, andesite and diorite (ca 1740–1660 Ma). The Ernest Henry hydrothermal system was formed by two cycles of sodic and potassic alteration where biotite–magnetite alteration produced in the first cycle formed ca 1514±24 Ma, whereas paragenetically later Na–Ca veining formed ca 1529 +11/−8 Ma. These new U–Pbtitanite age dates support textural evidence for incursion of hydrothermal fluids after the metamorphic peak, and overlap with earlier estimates for the timing of Cu–Au mineralization (ca 1540–1500 Ma). A distal to proximal potassic alteration zone correlates with a large (up to 1.5 km) K–Fe–Mn–Ba enriched alteration zone that overprints earlier sodic alteration. Mass balance analysis indicates that K–Fe–Mn–Ba alteration—largely produced during pre-ore biotite- and magnetite-rich alteration—is associated with K–Rb–Cl–Ba–Fe–Mn and As enrichment and Na, Ca and Sr depletion. The aforementioned chemical exchange almost precisely counterbalances the mass changes associated with regional Na–Ca alteration. This initial transition from sodic to potassic alteration may have been formed during the evolution of a single fluid that evolved via alkali exchange during progressive fluid-rock interaction. Cu–Au ore, dominated by co-precipitated magnetite, minor specular hematite, and chalcopyrite as breccia matrix, forms a pipe-like body at the core of a proximal alteration zone dominated by K-feldspar alteration. Both the core and K-feldspar alteration overprint Na–Ca alteration and biotite–magnetite (K–Fe) alteration. Ore was associated with the concentration of a diverse range of elements (e.g. Cu, Au, Fe, Mo, U, Sb, W, Sn, Bi, Ag, F, REE, K, S, As, Co, Ba and Ca). Mineralization also involved the deposition of significant barite, K(–Ba)–feldspar, calcite, fluorite and complexly zoned pyrite. The complexly zoned pyrite and variable K–(Ba)–feldspar versus barite associations are interpreted to indicate fluctuating sulphur and/or barium supply. Together with the alteration zonation geochemistry and overprinting criteria, these data are interpreted to indicate that Cu–Au mineralization occurred as a result of fluid mixing during dilation and brecciation, in the location of the most intense initial potassic alteration. A link between early alteration (Na–Ca and K–Fe) and the later K-feldspathization and the Cu–Au ore is possible. However, the ore-related enrichments in particular elements (especially Ba, Mn, As, Mo, Ag, U, Sb and Bi) are so extreme compared with earlier alteration that another fluid, possibly magmatic in origin, contributed the diverse element suite geochemically independently of the earlier stages. Structural focussing of successive stages produced the distinctive alteration zoning, providing a basis both for exploration for similar deposits, and for an understanding of ore genesis.  相似文献   
79.
地质单位财务管理咨询刍议   总被引:6,自引:0,他引:6  
宋建新 《中国煤田地质》2006,18(3):75-77,82
地质单位对自身无力解决的重要财务管理问题应该寻求外部咨询机构的有效帮助,针对地质单位财务管理中存在的主要问题提出需要咨询课题,而咨询机构通过对地质单位的财务状况进行调查分析后,提出科学、合理有效的财务管理改善方案和指导实施方案。  相似文献   
80.
尚洪田 《中国煤田地质》2006,18(4):25-26,52
分析了洪山预测区西部洪山岩体地质特征及其向外围扩散的范围和程度,研究了北掌勘查区和焦窑煤矿两邻区煤层受岩浆岩影响的程度,认为洪山岩体对预测区煤系及煤层赋存的影响较小,岩体外围仍有煤系赋存。为下一步找煤指明了方向。  相似文献   
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