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51.
52.
地下水氘过量参数的演化 总被引:18,自引:4,他引:18
本文详细地介绍了提出水体氘过量参数 (d值 )的依据、源于大气降水的地下水氘过量参数 (d值 )的演化特点、影响因素、误差来源 ,并分析和讨论了应用中的一些问题。 相似文献
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The Baimazhai nickel deposit, Yunnan Province, China, is located in the southern part of the Sanjiang (Tri-river) alkali-rich intrusive rock belt (Sanjiang ARIR). In this paper was conducted ^40Ar-^39Ar dating of two phlogopites in lamprophyres which are, as dikes, widely distributed in the orefield, and two plateau ages were acquired, i.e., 32.46±0.62 Ma and 32.01±0.60 Ma, respectively (averaging 32.23±0.60 Ma). The ages are obviously younger than those of the ore-hosted complex and mineralization of the Baimazhai nickel deposit. In combination with the characteristics, it is indicated that lamprophyres in the orefield and those in the Sanjiang ARIR are similar in tectonic setting, mineral assemblage and geochemistry. It is considered that lamprophyres in the orefield are the important component of the Sanjiang ARIR, and the lamprophyres and ore-hosted complex in the orefield represent the products of two times of different magmatic activity from different mantle sources. On the other hand, the age of lamprophyres in the orefield is older than that of the strike-slip shearing of the Ailaoshan-Honghe fault belt, suggesting that the strike-slip shearing of the Ailaoshan-Honghe fault belt is not the factor leading to magmatic activity of lamprophyres in the orefield, while it is more possible that magmatic activity of the Sanjiang ARIR promoted strike-slip shearing of the fault belt. 相似文献
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储层裂缝特征测井解释方法综述 总被引:20,自引:0,他引:20
为了更好地研究裂缝性砂砾岩储层和其它裂缝性储层裂缝的测井解释问题,综述了目前在裂缝性储层裂缝测井解释中主要采用的常规评价、人工神经网络和斯通利波3类方法在识别裂缝带和定量计算储层裂缝参数两个方面的应用原理和研究现状,并指出了今后的一些研究方向。 相似文献
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云南金平白马寨铜镍硫化物矿床含矿岩体为侵位在奥陶系砂页岩的镁铁-超镁铁环状杂岩体。从岩体核心到边缘依次出现橄榄岩—橄榄辉石岩—辉石岩—辉长岩的岩相分带。该岩体的主量元素显示拉斑玄武岩岩浆分异演化的趋势。REE显示富集LREE的配分模式,具明显的Eu异常。微量元素蛛网图显示明显的Ta、Nb、Ti及P的负异常。具有高(87Sr/86Sr)i(0.710974~0.722667)和低εNd(t)(-13.17~-12.09)的特征。微量元素和同位素地球化学证据表明,岩浆源于俯冲地壳物质改造的富集地幔,岩浆上升过程中遭受了一定的地壳物质混染。岩体可能是在弧后拉张的构造环境中形成。 相似文献
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Emergency response to water-related disasters is an important part of many coalmine operations in China. It usually consists
of both incident prevention measures and rescue counter-plans. In principle, prevention is always the top priority, followed
by rescue. The prevention measures relies on thorough understanding of the mine hydrogeology, correct identification of water
burst risk levels, and an effective monitoring program for inundations. The emergency rescue is initiated when an accident
occurs, and a rescue plan often includes a self-rescue and mutual-rescue program. 相似文献
58.
新疆库车盆地吉迪克组的地层时代和沉积环境 总被引:4,自引:0,他引:4
库盆地吉迪组分布十分广泛,它是储油层和油、气田的盖层,主要由碎屑岩或碎屑岩与石膏岩的互层组成,沉积厚度301.4-1081m。这套地层中富含有孔虫、介形类、抱粉、轮藻和腹足类等化石,通过古生物群的分折研究,可确定其沉积时代为中新世,更确切地说为中新世早、中期。通过沉积物特征和古生物群中广海、底栖有孔虫,咸水型介形类,水生植物抱粉和沟鞭藻等门类的分析,大致可确定沉积物的物源主要来自盆地北部的南天山山脉。沉积物颗粒自北向南由粗变细,水体中的含盐度自西向东逐渐升高,沉积了石膏、石盐和钙芒硝等盐类物质;推测在中新世早、中期库车盆地可能与塔里木盆地西部的喀什-乌恰-带残留海相连通。 相似文献
59.
Extremum solutions to the limit equilibrium method subjected to physical admissibility 总被引:2,自引:0,他引:2
In the slope stability analysis, the interslice force calculated by the method of slices is the internal force of the slope in the limit equilibrium state, which is vital to the design of reinforcement. However, none of the existing methods can guarantee a priori the interslice force is reasonable. Starting from the global analysis procedure, an optimization problem for maximizing the factor of safety is posed under the constraints that the system of forces in the sliding body is physically admissible. In the problem, both the factor of safety and the normal stress along the slip surface are taken as the independent variables. With weak nonlinearity and no numerical problems inherent in the methods of slices, the optimization problem can be solved by those conventional optimization techniques. No assumption is made regarding the interslice forces, but the system of forces from the optimization problem is physically admissible. To bracket the factor of safety, meanwhile, the minimum of the factor of safety is calculated through a minimization process under the same constraints as the maximization process. It is illustrated that for smooth slip surfaces, the solutions to the maximum and the minimum almost coincide, and for non-smooth slip surfaces, the interval of the solution is very narrow. 相似文献
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