大湾区珠江口海上高密度电法探测  

Marine Electrical Resistivity Tomography Research in Pearl River Estuary of Greater Bay Area

作　　者：陈斌[1] 汪耀 胡祥云[2] 李倩婕 Chen Bin;Wang Yao;Hu Xiangyun;Li Qianjie(Institute of Geological Survey,China University of Geosciences,Wuhan 430074,China;Institute of Geophysics&Geomatics,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]中国地质大学地质调查研究院,湖北武汉430074 [2]中国地质大学地球物理与空间信息学院,湖北武汉430074

出　　处：《地球科学》2020年第12期4550-4562,共13页Earth Science

基　　金：国家自然科学基金项目(No.41804122);珠江口伶仃洋地区综合地质调查项目(No.DD20190289);地质探测与评估教育部重点实验室主任基金;中央高校基本科研业务费项目(No.GLAB2020ZR10)。

摘　　要：海域环境对高密度电阻率法在仪器设备、测量技术和反演解译等方面提出了更高要求,开展海上高密度电法的数值模拟和实测研究将进一步丰富近岸海域地质、资源和环境等问题的勘查手段.基于数值模拟和野外实测,深入研究了偶极-偶极、温纳、斯贝等不同装置对近岸海域典型地电模型的分辨能力和空间定位效果,并详细分析了海水导电性的影响,最后在珠江口伶仃洋海域开展了国内首次2条长剖面的实际测量.结果表明海水电导率对不同测量装置在探测深度和精度方面存在差异化影响,井中电缆利用浮力材料固定后,进行水面拖缆式偶极-偶极测量能大幅降低海底沉缆式测量的施工风险,实现复杂海域环境下高密度电法探测效果、深度与效率的优化折中.Applying the electrical resistivity tomography(ERT) technique in the marine environment claims higher levels in the aspects of instrument, measurement techniques, inversion and interpretation methods and so on. The exploration approaches on issues of geology, natural resources and environment will be further enriched by numerical simulations and actual measurement research of the marine ERT in the coastal area. Based on numerical simulations and field measurements, in this paper it focuses on the research of the resolution and spatial location of the typical geo-electrical models in the offshore area with different arrays such as dipole-dipole, Wenner and Schlumberger. It also studied the effects of seawater conductivity and first conducted two long profile measurements at the site of Pearl River Estuary in the Lingdingyang area. It shows that the detection depth and resolution with different configurations would be differentially influenced by the conductivity of the seawater. And the construction risk of applying the boat-towed electrode arrays floating on the water and pulled behind a boat with borehole electrode cables and buoyant materials is much lower than a pulled-array on the seafloor. This will achieve a balance among the effect, depth and the efficiency for the ERT in the complex marine environment and finally promote the development and maturity of ERT technology.

关 键 词：大湾区 伶仃洋 近岸海域 海上高密度电法 海洋地球物理 

分 类 号：P319.2[天文地球—固体地球物理学]