【作者】 柴建峰；

【导师】 王景明； 王江帅；

【作者基本信息】 河北理工学院 ， 防灾减灾工程及防护工程， 2003， 硕士

【摘要】 河北平原地区是我国著名的强震带,地震灾害及地质灾害严重。自1949年来发生3次7级以上地震,特别是1976年唐山7.8级地震,人员伤亡达24余万人。随着河北省经济的高速发展,全面、科学的论证河北平原地区的地质环境和地壳稳定性、预测地质环境对区域工程建设和经济环境的影响、防治地质灾害发生,使该区土地规划和经济建设用地与地质环境相适应。“活断层评价与区域构造应力场分析”是区域地壳稳定性评价的重要内容。区域地壳稳定性概括地说,就是工程建设区或拟建区地壳及其表层的稳定程度。地震活动、断裂活动、火山活动及地壳形变是区域地壳稳定性研究的中心内容。本文在分析总结已有资料和现场考察的基础上,采用分段、分形分维相结合的方法,着重对研究区NE向及纬向活断层系进行分维计算,得出河北平原区NE向分维值为1.77,纬向活断层系分维值为1.41,全区分维值为1.68。河北平原区活断层系空间分维值较高,高于日本活断层系(1.50≤D≤1.60)和川滇西北活断层系(D≤1.5),这和研究区地震活动频繁、地质灾害多发一致。同时得出沧东断裂为铲式断裂,发育于上地壳,不是活动断层;唐山—河间—涉县地震带,具有统一的构造应力场,带内震源机制解具有一致性,是一条右旋剪切错动的地壳破裂带,是由一系列断裂组成,为不连续断裂。通过区域地质分析、地应力实测资料、震源机制解和有限元数值模拟3者相结合的方法。对区域构造应力场分析得出:应力集中区与地震密集分布区有很好的对应关系,说明有限元模拟地质模型具有合理性。如邯郸、邢台、唐山地区地震震中集中、密集,和应力场有限元数值模拟结果一致。更多还原

【Abstract】 Hebei Plain is one of severe earthquake places in China, and it is famous for its Seismic and Geological hazards. Since 1949 there have taken place three earthquakes whose Ms are all up to 7.0,in particular the Tangshan Earthquake (Ms=7.8 ) which took place in 1976 and nearly 240000 people died in this hazard. Along with the quick development of economy and science, it is vital to entirely evaluate the Geological environment and the stability of Crust, forecast the impact which is from the reaction between the Geological Environment and Engineering Construction and economic development, prevent and control the geological hazards in order to make well use of field.The Evaluation and Analysis of Active Fault and Regional Tectonic Stress Field is one of important parts of Analysis and Evaluation of Crust Stability. And Seismic activities, active faults, volcanic activities play great role in the Analysis and Evaluation of Crust Stability.Based on analyzing previous datum and reviewing active faults in point, and using subsection and fractal and fractal dimension to analyze the area, getting the fractal dimension of NE is 1.77,the fractal dimension of the direction of latitude is 1.41, the average fractal dimension of the area is 1.68, and the datum are higher than the active faults system of Japan and the fractal dimension of the northwest of Sichuang and Guizhou, the high fractal dimension is consistent with so many earthquakes and Geological hazards. At the same time making the conclusion that the Cangdong fault is not an active fault and is a shovel fault and is not possible for this fault to cause severe earthquakes. The Seismic strip of Tangshan-Hejian -Shexian has same Tectonic Stress Field and the Seismic Mechanism Solutions are nearly identical, and it is a sheared moving zone of Crust Fracture ,but it is not successive, it is made up of series faults.In this paper, using the measured datum of Stress, the Seismic Mechanism Solutions and the numerical stimulation by the Finite Element Method to analyze the Tectonic Stress Field. The Tectonic Stress is the prime impulsion of the Crust movement and distortion. And finding that the focus area of stress is corresponding to the dense area of earthquakes, which shows the Geological Model is reasonable and更多还原