Evaluation of Electrical Resistivity Tomography and Electromagnetic with Very Low Frequency Method in Identifying Buried Karst in Shaho Rifts (The Case of Quri Qaleh Cave)

Karst and karst cavities are one of the most challenging subjects. Given that karst areas cover approximately 20% of the land area, Identifying and investigating the location of karst buried cavities can be useful in various usages such as tourism development, subsidence prevention and karst water resources. In the rifts of Shaho, located in Kermanshah province, karst landforms, including caves and buried cavities, are well stretched. The current study attempted to identify rapid and early karst cavities using an easy and low-cost method in geomorphological studies. To this end, in Shaho rifts (Quri Qaleh cave and its surroundings), two geophysical methods namely Electrical Resistivity Tomography (ERT) and Very Low Frequency Electromagnetism (VLF) were utilized and compared. Initially, by determining the location of the cave on the ground, the profile performing route was designed perpendicular to the cave route. Then, 5 profiles were performed by VLF and 4 profiles by ERT method. Four ERT profiles perpendicular to profiles 2, 4 and 5 of VLF were taken and finally the results of the two methods were compared. In addition to determining the exact location of the cave, the results of both methods revealed anomalies outside the cave. Other findings of the research include the possibility of rapidly achieving the results and the cheaper use of the VLF method compared to other identification methods.