Identification of underground freshwater bodies in coastal areas based on high-density resistivity

The identification of underground freshwater bodies can assist us effectively to find freshwater resources in coastal areas. In this article, we present the theoretical basis of high-density resistivity method for identifying freshwater bodies in coastal areas. The result shows that the method could distinguish the freshwater-saltwater interface, with which freshwater layer can be clearly shown on the profile of high-density resistivity inversion, from which freshwater distribution can be effectively delineated. In addition, the results agree well with the hydrogeological survey results, indicating that this method is feasible and effective in coastal areas. At last, the electrical characteristics and vertical distribution of freshwater bodies were summarized. This study provided reliable basic data for regional hydrogeological survey and exploration.