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目的 说明地球层析成像一词的含义和它所包括的分支有:地震层析,电阻率层析,大地电磁层析,磁共振成像, 地震破裂面照相以及探地雷达成像等。概括当前这几种手段的成就,所能达到的成像精密度, 用现代的计算方法、反演地下介质速度、衰减 Q值、密度、孔隙度分布、介质破裂程度,可提高震源定位精度,再借鉴医学上检测癌细胞发生、发展过程的模式,建立相应的预测模式。判断未来破坏性地震的孕震结构,发展趋势,以及地下水与电阻率图像随季节变化的关系。初步阐明地球层析成像在减轻地震灾害、洪水灾害与火山喷发灾害中的作用。将地电阻率层析与磁共振测深成像相结合应用于探测地下水的一些基本分布特征,判定潜伏断层的特征,追踪电阻率异常区其附近的电性精细结构,分辨率可以达到 1 米左右。结合起来可探测地下裂隙分布,发现活断层,对高层建筑物(80 米以上)和大型桥梁、水坝、堤防的安全性评价具有重要作用,以便及早加固,以减轻损失;结论 利用上述地球层析成像的几种手段,可以探测地下活动断层、孕震结构和地下水与电阻率随季节的变动,为判定高楼和堤坝的安全性提供依据,在减轻灾害中发挥日益重要的作用。
Objective To explain the meaning of the term earth tomography and the branches it includes: seismic tomography, resistivity tomography, magnetotellurography, magnetic resonance imaging, seismic rupture surface photography and ground-based radar imaging. Summarizes the achievements of these kinds of methods, the imaging precision that can be achieved, using modern calculation methods, inversion of the velocity of underground media, attenuation of Q value, density, distribution of porosity and degree of media rupture, can improve the positioning accuracy of the hypocenter Learn from the medical detection of cancer cells, the development process of the model, the establishment of the corresponding prediction model. The seismogenic structure of the future devastating earthquakes, the trend of development, and the relationship between groundwater and resistivity images with the seasons are also analyzed. Preliminary clarify the role of earth tomography in mitigating earthquakes, floods and volcanic eruptions. The combination of resistivity tomography and magnetic resonance sounding imaging can be used to detect some basic distribution features of groundwater and determine the characteristics of latent faults and to track the electrical fine structure in the vicinity of the resistivity anomaly area with a resolution of up to 1 meter . Combining to detect the distribution of underground fractures, it is found that the active fault plays an important role in the safety assessment of high-rise buildings (over 80 meters) and large bridges, dams and embankments, so as to reduce the losses as early as possible. CONCLUSIONS: Several means of imaging can detect subsurface activity faults, seismogenic structures and groundwater and resistivity changes with the seasons, and provide basis for judging the safety of tall buildings and dams, playing an increasingly important role in disaster mitigation.