二维地震和高密度电阻率测深揭示雄安新区浅部三维地质结构特征

雄安新区位于冀中平原中部,地下结构具有新生界地层厚度大、成层性好、构造活动相对稳定的显著特点。为精细刻画浅层地质结构,查明断裂构造特征,提高浅部探测精度,本次研究采用二维地震和高密度电阻率测深结合的方法,取得了重要进展,主要包括:①精细刻画了工作区200 m以浅深度范围内地层结构和断裂构造空间展布特征;②构建了三维可视化地质结构模型,直观展示了调查区新生界地层起伏形态和主要断裂构造空间分布;③分析总结了城镇化高干扰背景环境下地球物理方法的探测深度、横纵向分辨率、目标体响应特征和适用性等。本次研究有效支撑和服务了雄安新区的规划、建设以及地下空间开发利用,对大厚度沉积盆地城市地下空间的地球物理探测具有借鉴意义。

2D seismic and high-density resistivity sounding reveal the shallow three-dimensional geological structure characteristics of Xiong'an New Area

The Xiong'an New Area is located in the middle part of the Jizhong Plain.The Cenozoic strata in the underground structure of the area have a large thickness,good stratification,and relatively stable tectonic activities.To finely determine the shallow geological structures,ascertain the fault structure characteristics,and improve the shallow exploration accuracy,this study combined two-dimensional seismic surveys and high-density resistivity sounding and made the following important progress.①This study finely determined the geological structure and the spatial distribution characteristics of fault structures at a depth of less than 200 m in the Xiong'an New Area;②This study constructed a three-dimensional visualized geological structure model,which intuitively displays the stratigraphic fluctuation pattern of Cenozoic strata and the spatial distribution of main fault structures;③This study analyzed and summarized the application of geophysical methods under the background of urbanization-induced high disturbance,including their exploration depths,horizontal and vertical resolution,response characteristics of geological bodies,and applicability.This study effectively supports and serves the planning,construction,and underground-space development and utilization in the Xiong'an New Area and serves as a reference for the geophysical exploration of urban underground space in hugely thick sedimentary basins.