北部湾咸淡水分界面划分中的电法应用分析

Application analysis of electrical method in dividing saltwater and freshwaterinterface in beibu bay

北部湾地区海水入侵现象较为普遍,海水入侵造成的影响较为明显,制约了当地的城市规划和建设,因此,本文主要探测海水侵染的区域、划分咸淡水界线,为北部湾地区水文地质调查提供基础资料.本文阐述了高密度电法是海水入侵探测方法中一种重要的地球物理手段,从原理及技术参数上做了详细的介绍,并以北部湾近郊区及北海市区典型的海水侵染地段作为实例进行了对比探讨,通过分析实测的视电阻率数据及电阻率反演数据,结果表明:高密度电法可以有效的圈定海水侵染的大致区域,识别咸淡水的空间分布界线,给出海水入侵的空间展布形态,其结果与水文地质钻孔资料和民井调查资料基本吻合.通过本文总结:高密度电法具有点距小、数据密度大、施工便捷、结果反应直观、快速高效的特点,在北部湾海水入侵调查中可以作为主要的技术手段进行广泛应用.

The phenomenon of seawater intrusion in the Beibu bay is much common,and the impact of seawater intrusion is relatively obvious,which is restricting the planning and construction of the local city.Therefore,this paper mainly explores the area of seawater infestation the boundary of saltwater and fresh water,providing basic data for hydrogeological investigation in Beibu bay area.This paper expounds that high density resistivity methods are an important geophysical means in seawater intrusion detection,and gives a detailed introduction to the principles and technical parameters.In this paper,a case study is carried out in the suburb of Beibu bay and the typical seawater infecting area in the urban area of Beihai,by analyzing the measured apparent resistivity data and resistivity inversion data.As the results show,high density resistivity method can effectively delineate the approximate area of seawater infection and identify the spatial distribution boundary of saltwater and freshwater,and give the spatial distribution pattern of seawater intrusion,the results of which are in accordance with the hydrogeological borehole data and civil well survey data.Throungh the summary of this article,some conclusions can be drawn:the high density electricity method has the the characteristics of small distance,large data density,convenient construction,directing response to the result and high efficiency,which can be widely used as a main technical means in the investigation of seawater intrusion in the Beibu bay.