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从构造模拟目标、构造模型建立、构造模拟三个方面探讨了古构造应力场数值模拟的方法。以山西省晋城成庄煤矿区为例, 根据野外调查和微观构造形迹, 建立平面应力模型和三维地质模型, 确定岩体力学参数、边界条件及岩石破裂准则, 采用大型数值模拟软件ANSYS和FLAC计算, 确定外力的大小及加载顺序。通过分析研究, 揭示了山西晋城成庄煤矿区历史上曾发生先东西向、后南北向的两期大的构造运动, 加载外力为先东西向加载60 MPa, 再南北向加载110~180 MPa, 这个结果能解释多数地表剪节理和3#煤中剪节理同时发生。该分析对矿区的危险性分区及瓦斯突出区的预测具有重要的意义。 相似文献
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South China is the most important uranium producer in the country. Much of the Mesozoic-Cenozoic geology of this area was
dominated by NNE-trending intracontinental strike-slip faulting that resulted from oblique subduction of the paleo-Pacific
plate underneath the eastern China continent. This strike-slip fault system was characterized by transpression in the early-mid
Jurassic and by transtension from the latest Jurassic through Cretaceous to early Tertiary. Most uranium ore deposits in South
China are strictly fault-hosted and associated with mid-late Mesozoic granitic intrusions and volcanic rocks, which formed
under transpression and transtension regimes, respectively. Various data demonstrate that the NNE-trending strike-slip faults
have played critical roles in the formation and distribution of hydrothermal uranium deposits. Extensive geochronological
studies show that a majority of uranium deposits in South China formed during the time period of 140–40 Ma with peak ages
between 87–48 Ma, coinciding well with the time interval of transtension. However, hydrothermal uranium deposits are not uniformly
distributed along individual strike-slip fault. The most important ore-hosting segments are pull-apart stepovers, splay structures,
extensional strike-slip duplexes, releasing bends and fault intersections. This non-uniform distribution of ore occurrences
in individual fault zone reflects localization of hydrothermal fluids within those segments that were highly dilational and
thus extremely permeable. The unique geometric patterns and structural styles of strike-slip faults may have facilitated mixing
of deeply derived and near-surface fluids, as evidenced by stable isotopic data from many uranium deposits in South China.
The identification of fault segments favorable for uranium mineralization in South China is important for understanding the
genesis of hydrothermal ore deposits within continental strike-slip faults, and therefore has great implications for exploration
strategies. 相似文献
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水力压裂角砾岩：一种重要的地质异常和找矿标志 总被引：1，自引：0，他引：1
水力压裂作用是地壳内的一种重要变形破裂方式，许多热液脉体和热液矿床直接受其控制，以华南金银寨大型负矿床为例，详细介绍了水力压裂角砾岩和裂隙一脉的几何特征，鉴别标志和形成机制，水力压裂角砾岩不仅是一种重要的地质异常，而且常伴随不同程度的金属矿化而使之成为一种重要的矿化体和找矿标志。 相似文献
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液压致裂作用及其研究意义 总被引：8，自引：1，他引：8
介绍了液压致裂的力学机制和对流压致裂的数学模拟结果，总结了液压致裂裂隙－脉－角砾岩系的订鉴别特征。 相似文献
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从岩土体性质、地下水、时间效应、深度、桩截面尺寸及桩周地基土的变形量方面,讨论了影响地基系数的几个因素,给出了线弹性地基反力法计算弹性桩内力的通解,比较了几种线弹性地基反力法的分布形式、适用条件及其不足之处.以三峡库区万州区二层岩滑坡为例,对于3种不同地质环境中的抗滑桩分别采用K法、C法、M法计算抗滑桩的内力,结果表明:M法计算得到的抗滑桩承受的弯矩、剪力最大,桩水平位移最大,对桩周岩土体的应力最小;K法计算得到的弯矩、剪力最小,桩水平位移最小,对桩周岩土体的应力最大.根据万州区滑坡抗滑桩嵌岩段岩土体的质量等级,认为万州区抗滑桩设计采用M法较适宜,这对万州区今后滑坡治理设计具有重要的指导作用. 相似文献
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