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81.
根据矿床地质特征、成矿温度、成矿时代及成矿物质来源等方面的研究,认为本矿床成矿流体来源于地慢岩浆水,并有海水混入。成矿物质主要来源于深部地壳和地慢,通过同生断裂喷气—喷流作用,在有利的地层和物理化学条件下沉淀成矿。矿床成因属于同生断裂喷流热液层控矿床。  相似文献   
82.
InSAR用于南极测图的可行性研究   总被引:10,自引:1,他引:10  
利用1996年ERS-1/2tandem方式的雷达影像数据进行了生成Grove山数字高程模型的试验研究,并与实测的DEM进行比较分析,论证了利用InSAR技术进行南极测图的可行性。试验证明,在南极研究中,InSAR是一种非常有效的手段,不仅可用于地图制图,而且在冰川动力学、冰貌环境变化等研究领域也有巨大的潜力。  相似文献   
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84.
白云岩成岩收缩晶间孔、洞、缝与构造网状缝相互沟通可以组成良好的油气储层,但是这种复杂裂缝—孔隙型储层分布随机性强、发育程度和差异性大,储层预测难度大。本文以中国西部酒泉盆地青西油田下白垩统下沟组湖相白云岩裂缝—孔隙型储层为例,提出地球物理综合预测碳酸盐岩裂缝的方法。本文描述了综合地球物理方法预测碳酸盐岩裂缝储层的实施和应用效果。  相似文献   
85.
据岩体在卸荷情况下的拉剪应力状态,确定了节理岩体的线弹性断裂力学模型。依照此模型,可以得到相对远离裂隙(该位置的点到裂隙中心的距离比裂缝长度大)且受裂隙影响区域内应力、应变和变形方程。这些对评估裂隙岩石变形有重要的参考意义。通过用理论方程的计算结果和卸荷情况下试验观测所得的数据对比,证明该模型应用于实际工程中具有可行性。  相似文献   
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87.
The locations of mining-induced horizontal fractures along rock interfaces in the overburden of Donetsk Coal Basin were identified using an original experimental device. The device traps methane from horizontal fracture zone (100–fold coal seam thickness) over an active longwall mining excavation. Presence or absence of horizontal fractures along rock layer interfaces is correlated with physical characteristics of the overburden, such as thickness, uniaxial compressive strength of overburden rock layers, location of rock layer interfaces and thickness of extracted coal seams. As a result, a combined criterion based on these physical characteristics is proposed to predict the presence of overburden horizontal fracturing in coal mine operations.  相似文献   
88.
This study evaluates the susceptibility of landslides in the Lai Chau province of Vietnam using Geographic Information System (GIS) and remote sensing data to focus on the relationship between tectonic fractures and landslides. Landslide locations were identified from aerial photographs and field surveys. Topographic, geological data and satellite images were collected, processed, and constructed into a spatial database using GIS data and image-processing techniques. A scheme of the tectonic fracturing of crust in the Lai Chau region was established. Lai Chau was identified as a region with many crustal fractures, where the grade of tectonic fracture is closely related to landslide occurrence. The influencing factors of landslide occurrence were: distance from a tectonic fracture, slope, aspect, curvature, soil, and vegetative land cover. Landslide prone areas were analyzed and mapped using the landslide occurrence factors employing the probability–frequency ratio model. The results of the analysis were verified using landslide location data and showed 83.47% prediction accuracy. That emphasized a strong relationship between the susceptibility map and the existing landslide location data. The results of this study can form a basis stable development and land use planning for the region.  相似文献   
89.
Summary To understand the failure mechanism of quasi-brittle materials like rock under tensile stress, observations on the failure process of granite and marble plate specimens under tension are summarized and presented. Micro- and macro-failure properties of rock plates under uniaxial tension have been characterized by using an acoustic emission technique. Acoustic emission signals associated with micro-fractures are captured to locate the sources. An algorithm based on arrival time difference is developed for this purpose. The results reveal clearly the failure processes of rock which include initiation, nucleation and propagation of micro-fractures when the axial stress is close to the peak strength of rock. It is believed that the difference in heterogeneity between granite and marble specimens leads to different fracture shapes and different behaviors of associated acoustic emissions. Numerical simulation of acoustic emissions for two-dimensional tensile test is also carried out. The simulated characteristics are in good agreement with the experimental results.  相似文献   
90.
The effects of fractures on wave propagation problems are increasingly abstracting the attention of scholars and engineers in rock engineering field. This study aims to fully validate the ability of discontinuous deformation analysis (DDA) to model normal P‐wave propagation across rock fractures. The effects of a single fracture and multiple parallel fractures are all tested. The results indicate that DDA can accurately reflect the fracture effects, including the fractures stiffness, the fracture spacing and the fracture number, and the effects of incident wave frequency on one‐dimensional P‐wave propagation problems. Thus, DDA is able to deal well with normal incident P‐wave propagation problems. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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