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81.
利用相控模型进行井间参数预测   总被引:18,自引:0,他引:18  
桂峰  马正 《地球科学》2001,26(1):49-53
储层物性参数在空间的展布,一直是储层非均质性研究的难点,利用分形和蒙特卡洛方法,在精细的沉积微相及小层对比研究基础之上,预测了井间的岩石相分布,并根据取心井资料,建立了各种岩石相的渗透率相控模型,从而预测出井间渗透率的分布。该方法以地质特征为基础,将地质资料与数学方法相结合,充分体现了渗透率在井间既具有连续性,同时变化又非常剧烈的特点,为储层物性空间预测提供了新的思路。  相似文献   
82.
吴凤鸣 《吉林地质》2001,20(4):4-6,32
面对资源、环境、人口、地质灾害等人类的生产、生活乃至生存的严峻危机,需要我们掌握地球内部的客观规律,不断更新和寻找地球科学理论和新的思维方式,掌握地球科学发展趋势,以协调好人与自然、人地关系及社会经济和可持续发展理论,造福于人类。  相似文献   
83.
安徽巢湖凤凰山晚古生代大冰期沉积特征与碳同位素变化   总被引:1,自引:0,他引:1  
地史中海相碳酸盐岩记录的无机碳同位素的波动经常与全球气候事件相互关联,但碳酸盐岩的碳同位素不仅与全球碳循环相关,也受控于区域水循环和成岩作用.晚古生代大冰期在石炭纪末—早二叠世达到最高峰,南方冈瓦纳大陆高纬度地区冰川的进退引起低纬度地区旋回性的海平面变化,并发育显著的沉积间断,在华南表现为喀斯特岩溶角砾岩等.本文选取安...  相似文献   
84.
目前关于思茅地块西缘大凹子组的形成时代仍有分歧.在思茅地块西缘大中河剖面采集了硅质岩、砂岩、凝灰岩和玄武岩,通过放射虫组合和锆石U-Pb年龄方法,厘定其地质时代,并结合区域资料恢复地层序列.通过详细剖面实测,发现该剖面由6个地层断片组成:第一、四断片以含放射虫硅质岩为特征,放射虫组合指示其时代为晚泥盆世至早石炭世早期;第二、五断片以火山碎屑岩、具有鲍玛序列沉积特征的火山碎屑沉积岩为主,锆石U-Pb同位素年龄指示其时代为志留纪中期至早泥盆世;第三、六断片以火山岩沉积为特征,锆石U-Pb同位素年龄指示其时代为志留纪早期.结合前人资料认为思茅地块西缘分布的海相火山岩、碎屑岩和含放射虫硅质岩地层层序代表了志留纪到早石炭世早期的岛弧火山-沉积地层序列.  相似文献   
85.
在苏南某工业厂房扩建工程中,为了妥善解决新旧熔炉区的不均匀沉降,通过多方案的比选,最终采用树根桩托换技术进行地基加固。并且对新旧熔炉区的基础进行了化学植筋连接和防渗漏处理。  相似文献   
86.
龙锋  倪四道  闻学泽 《地球学报》2011,32(4):438-446
利用龙门山断裂带及其邻近地区地震台站的远震波形记录,采用时间域迭代反褶积技术求取接收函数,并用H-Kappa叠加方法计算出各台站下方的莫霍面深度和波速比及其相应的误差.结果除了获得与前人研究大体相同的莫霍面深度分布轮廓外,还获得一些新的细节与认识:(1)莫霍面深度在四川盆地内为41~48 km,在四川盆地西缘存在一个N...  相似文献   
87.
88.
塔里木盆地内地表面巨厚的沙层是油气勘探的主要障碍。本文在构造解释中用切除法把地表面低速的、不稳定的沙层切除,然后通过折射波反演方法,得其厚度,从而提高了构造图的精度。  相似文献   
89.
The Middle-Lower Yangtze (Changjiang) River Valley metallogenic belt is located on the northern margin of the Yangtze Craton of eastern China. Most polymetallic deposits in the Changjiang metallogenic belt are clustered in seven districts where magmatism of Mesozoic age (Yanshanian tectono-thermal event) is particularly extensive. From west to east these districts are: E-dong, Jiu-Rui, Anqing-Guichi, Lu-Zong, Tong-Ling, Ning-Wu and Ning-Zhen. World-class iron ore deposits occur in the Lu-Zong and Ning-Wu ore clusters, which are mainly located in continental fault-bound volcanic-sedimentary basins. One of these deposits is the Longqiao iron deposit, discovered in the northern part of the Lu-Zong Basin in 1985. This deposit consists of a single stratabound and stratiform orebody, hosted in sedimentary carbonate rocks of the Triassic Dongma'anshan Formation. A syenite pluton (Longqiao intrusion) is situated below the deposit. The iron ore is massive and disseminated and the ore minerals are mainly magnetite and minor pyrite. Wall rock alteration mostly consists of skarn minerals, such as diopside, garnet, potassic feldspar, quartz, chlorite, phlogopite and anhydrite. Thin sedimentary siderite beds of Triassic age occur as relict laminated ore at the top and the margin of the magnetite orebody. These sideritic laminae are part of Triassic evaporite-bearing carbonate deposits (Dongma'anshan Formation).Sulfur isotopic compositions show that the sulfur in the deposit was derived from a mixture of magmatic hydrothermal fluids and carbonate–evaporite host rocks. Similarly, the C and O isotopic compositions of limestones from the Dongma'anshan Formation indicate that these rocks interacted with magmatic hydrothermal fluids. The O isotopic compositions of the syenitic rocks and minerals from the deposit show that the hydrothermal magnetite and skarn minerals were formed from magmatic fluids. The Pb isotopic compositions of sulfides are similar to those of the Longqiao syenite. Phlogopite coexisting with magnetite in the magnetite ores yielded a plateau age of 130.5 ± 1.1 Ma (2σ), whereas the LA-ICP MS age of the syenite intrusion is 131.1 ± 1.5 Ma, which is slightly older than the age of phlogopite.The Longqiao syenite intrusion may have crystallized from a parental alkaline magma, generated by partial melting of lithospheric mantle, during extensional tectonics. The ore fluids were probably first derived from magma at depth, later emplaced in the sedimentary rocks of the Dongma'anshan Formation, where it interacted with siderite and evaporite-bearing carbonate strata, resulting in the formation of magnetite and skarn minerals. The Longqiao iron deposit is a skarn-type stratabound and stratiform mineral system, genetically and temporally related to the Longqiao syenite intrusion. The Longqiao syenite is part of the widespread Mesozoic intracontinental magmatism (Yanshanian event) in eastern China, which has been linked to lithospheric delamination and asthenospheric upwelling.  相似文献   
90.
Landslides are the major natural hazards in many countries all over the world and are usually caused by heavy rainfall, water level change of reservoir, excavation, earthquake, etc. Whether the landslide occurs or not in rainfall season, the strength variation of slip-zone soils of landslide is regarded as the vital control factor. Thus, strength behavior for slip-zone soils of landslide subject to the change of water content is required to be evaluated in a potential landslide area. In this paper, the shear strength of typical slip-zone soil, six groups of 25 specimens of remolded clay samples from Daxishan reservoir landslide, was systemically investigated using the improved direct shear test apparatus in order to fully understand its physical and mechanical properties, and also the shear and failure behavior. Furthermore, the fitting equations for expressing the relationship between the shear strength (effective cohesion and internal friction angle) and vertical loadings, initial water contents of slip-zone clay were established based on the experimental results. In particular, a series of shear stress–shear strain curves under various vertical loadings and different water contents were observed. The results show that a “softening” stress–strain behavior is achieved for unsaturated slip-zone soil, while a “hardening” curve is found for saturated slip-zone soil.  相似文献   
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