• 责任者：He Fubing (Beijing Institute of Geological Survey ; Beijing 100195 ; China) ; Bai Lingyan
• 刊名：Seismology and Geology
• 出版年：2013
• 卷期：35(3)
• 关键词：断裂带 ; fracture zones ; 北京 ; Beijing
• 页码：p.490-505
• 图表：3 illus., 2 tables, 30 refs.
• 分类号：0300
• issnNo：ISSN0253-4967
• isbnNo：CN11-2192/P

     Xiadian Fault zone is a NNE-trending lithospheric-scale regional deep fault in the eastern part of the capital, also an active fault zone with strong earthquake activities in the history. According to the results of gravity,shallow seismic and high-density electrical geophysical prospecting, by ＂relay stitc- hing＂ vertically from the deep to the shallow ,and in combination with the methods of drilling and oth- er means,the Xiadian Fault zone is studied by dividing it into two parts： the bedrock fault zone and the Quaternary fault zone, and new insights are gained on the characteristics of deep structure and ac- tivity of the Xiadian Fault zone. The results show that ： （ 1 ） the bedrock fault zone of Xiadian Fault consists of main faults and secondary faults. Its northern part, the Mafang-Xiji area, is composed of two major faults with a narrower width, and the southern part, the Xiji-Fengheying area, is composed of three major faults,with a wider width; （2）The Quaternary fault zone of Xiadian Fault is the upward extension of the bedrock fault zone,which is the visual representation of the latest activity of the fault zone and controlled by the bedrock fault zone. The Quaternary fault zone is also composed of main faults and secondary faults. The northern part（Mafang-Xiji area） consists of two major faults and sec- ondary faults distributed in the northern end,corresponding well with the bedrock fault zone. Occur- rence of the two major faults is quite different, and the latest movement of the faults is both in Hol- ocene. While, the southern part of the fault zone（ the Xiji-Fengheying area）is quite discontinuous and is difficult to distinguish between the major and secondary faults. The faults have poor correspondence to the bedrock ones and are inferred to be related with the segmentation of faulting of the bedrock faults. Both major and secondary faults are steep and the date of their latest movement is late Pleisto- cene-early Holocene; （3）The amount of vertical dislocation of the bottom boundary of the Holocene sediments in the hanging and foot walls of Xiadian Fault zone is 1.7 -4.8m,and that of late, middle and early Pleistocene are 6 -26m,26 - 167m and 44 ~ 330m, respectively. The vertical dislocation on the whole fault zone differs greatly,with the highest in the Xiadian area, and decreasing gradually to the south and north ends ; （4） Considering the spatial distribution, structure, occurrence, activity and characteristics of seismic activity along of the fault zone, the Xiadian Fault zone is divided into the southern and northern segments with the Zhangjiawan Fault as the boundary. The northern part expe- rienced intensive Quaternary activity, with frequent moderate and small earthquakes. Quaternary activ- ity is weak along the southern part,where only small earthquakes occurred.