The Shijiazhuang City in Hebei Province lies at the junction between the Taihangshan uplift in the west and the Jizhong depression of North China in the east, abutting the front-range fault zone of the Taihangshan in the west. The Xingtai M7. 2 earthquake of March 1966 occurred southeast to this area. In October 2010, a broadband magnetelluric ( MT) survey was conducted in the Shijiazhuang City and adjacent regions to probe the deep structure. The 167km-long MT profile began from the Niangziguan town, extended southeastward through southern Shijiazhuang City, and terminated at Wangchang town of Jixian county. MT data were collected at 64 sites along this profile. In MT data processing, in addition to the remote reference and robust techniques, the multi-point and multi-frequency tensor decomposition was employed to determine the regional electric strike,and the NLCG 2D inversion was performed on TE and TM data. The result shows that a combination of an east-dipping low-angle normal fault in the shallow subsurface and a steep electric boundary at depth characterizes the deep structure beneath the study area. The electric structures in the shallow crust (above 10km) and deep crust ( below 10km) seem to be independent. The Jinxian Fault and Xinhe Fault extend to a depth of less than ~7km. High conductivity layer (HCL) is present below the depth of 10km between the front-range fault zone of the Taihangshan and the Xinhe Fault. There is a low resistivity boundary zone below the HCL and it cuts through the Moho. The hypocenter of the 1966 Xingtai Baichikou strong aftershock is located at the linkage between Xinhe Fault and deep electrical boundary,and on its top is a high resistance body and below it is the high conductivity layer(HCL). The HCL and the deep low resistivity boundary zone below the HCL are a channel of deep thermal upwelling and elastic energy migration. The 1966 Xingtai earthquake swarm is closely related to the deep material damping.%石家庄位于太行山隆起带和华北平原冀中坳陷盆地接触区,西邻太行山山前断裂带,1966年在其东南曾发生邢台7.2级强震.为研究该区的深部构造背景,并为分析地震活动性趋势提供基础资料,2010年10月采用宽频带大地电磁法对该区的深部结构进行探测研究.大地电磁剖面穿过石家庄南侧区域,长约167km,获得了64个测点数据.采用远参考和Roubst技术进行数据处理,使用多点、多频率GB张量分解方法计算分析区域的电性走向,使用NLCG二维反演方法对TE和TM模式进行联合反演,获得深部电性结构.太行山山前断裂带浅部东倾的低角度滑脱断层和深部陡立西倾的电性边界带,构成了太行山隆起带和华北平原冀中坳陷接触区的深、浅构造的组合形态；太行山山前断裂带东侧深(10km以下)、浅部(10km以上)结构具有相互独立性,冀中坳陷内的晋县断裂、新和断裂延伸深度不超过10km；邢台百尺口6.2级强余震震源位于上陡、下缓的新河断裂和其下隐伏的深部电性差异带的交会区,交会区上方及其东西两侧为具一定厚度和宽度的高阻体.在太行山山前断裂和新河断裂之间的中下地壳存在高导层,其中心对应石家庄-晋县凹陷.高导层中心部位比东西两侧浅,推测与深部热物质的上升有关.1966年邢台地震群就发生在该地区附近.
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