【作者】 马向贤；

【导师】 梁收运；

【作者基本信息】 兰州大学 ， 地质工程， 2010， 硕士

【摘要】 断层泥作为断层活动的产物,记载着断层活动的丰富信息。对断层泥的物质组成、结构特征及其反映的断层活动性、物理力学性质等许多方面的研究已经积累了大量成果。探索断层泥地球化学特征所反映的演化过程是地质学基础研究的前沿领域。选取青藏高原东北缘的3条断裂带的典型剖面,进行系统采样,开展XRD、XRF实验研究断层泥的矿物化学成分,应用MAT271质谱计测量断层泥吸附气体,首次应用大型同步辐射装置实验研究断层泥的锰和硫元素化学种。结合收集的研究资料,分析了断层泥物质组成特征,探讨了断层泥反映的形成环境和工程地质意义。主要研究成果如下：(1)矿物化学成分测试结果显示一般断层泥都含有石英、方解石和长石等造岩矿物,同时含有伊利石、高岭石、蒙脱石和白云母等粘土矿物。化学成分一般含有硅、钙、铁、硫、锰、镁和磷等元素,其中硅、铁和钙较为活泼。钙与镁、锰、硅,铝与钾、钛等具有较高的相关性。(2)对断层泥吸附气体的测试结果表明样品中气体含量CO2>N2>H2>CH4 (C2H6或C3H8)>C4H10,不含H2S,黑色断层泥中的吸附气体比黄色断层泥中的吸附气体含量多。发现断层泥吸附气体含量和断层活动历史有一定的相关性。(3)锰和硫元素化学种反映出红色和黄色断层泥一般含氧化性元素化学种,显示在氧化环境中形成,灰绿色和灰蓝色断层泥多含有还原性化学种,指示在还原环境中形成。(4)通过查阅大量的断层泥结构方面的资料,分析了断层泥的粒度特征和微观结构。尝试应用经典沉积物粒度分析法对断层泥的粒度特征进行了分析,建立了粒度参数和断层泥物理力学参数的关系。更多还原

【Abstract】 As a product of fault, fault gouge may contain a wealth of information about the activity. A huge mass of data have been accumulated on the material compositions and structure characteristics of fault gouge, as well as on the fault activity reflected, physical and mechanical properties. Exploring geochemical characteristics of fault gouge which reflected evolution process is basic research in frontier field of geology.Typical sections of the three faults near the northeastern Tibet plateau have been selected to systematic sampling in field study. The samples would be tested with experiments with XRD, XRF, and measurement of gas adsorption with MAT271 mass spectrometer, first applied BSRF to study S and Mn chemical species. The characteristics of the compositions of fault gouge and its environment of formation and engineering geological significance have been analyzed and discussed based on the experimental results and previous studies and findings. The major results are as follows:(1) The mineral and chemical composite experimental results showed that quartz, calcite and feldspar, and other rock-forming minerals are contained in fault zone, besides, there is a certain amount of clay minerals, such as illite, kaolinite, montmorillonite, muscovite and so on. From the analysis of the chemical constituents, we see that the Si, Ca, Fe, S, Mg, Mn and P et al. are contained in fault gouge, the more active elements are Si, Fe and Ca. A study of the correlation of elements in the samples reveals that Ca and Mg, Mn, Si; Al and K, Ti have high correlation.(2) From the experimental results of a test for adsorbed gas in fault gouge, it showed that CO2>N2>H2>CH4 (C2H6 or C3H8)>C4H10, and there is a correlation between content of adsorbed gases and history of fault activity.(3) Analyses of an X-ray absorption fine structure experiment with manganese and sulfur shows that the red and yellow gouge are usually formed in an oxidizing environment for they generally contain Oxidative chemical species; the gray-green and blue-gray gouge are formed in a reducing environment for they contain more reducing species.(4) By consulting a large number of structural data in fault gouge, we have analyzed the characteristics of particle size and micro-structure of the fault gouge. In this paper, the researcher tries to apply classic sediment particle size methods to analyze the characteristics of the fault gouge, the correlation between the particle size parameters and physical & mechanical parameters of fault gouge has been established.更多还原