Integrating geophysical methods in determining the geophysical parameters for subsurface structures

Abstract

This research aims to determine the geophysical parameters differences for the subsurface structures. In particular, two geophysical methods employed were 2-D Resistivity Imaging and Ground Penetrating Radar (GPR). The 2-D Resistivity Imaging data was inverted and interpreted using RES2DINV and Surfer8 software while the GPR data was processed using MALA Ground Vision software. Concrete structure and sediment-filled cavity can be compared based on the attenuation value of EM wave obtained from GPR method. Research was conducted at two study areas which are located at Universiti Sains Malaysia (USM) and Gunung Baling. Within USM, investigations were conducted at two sites to analyze geophysical parameters of the concrete structure while in Gunung Baling was to analyze geophysical parameters of sediments-filled cavity. The geophysical parameters results obtained from Gunung Baling are then compared with the results at USM. It was found that all study areas exhibit low resistivity value and have the same hyperbolic curve. However at USM, the attenuation value of electromagnetic (EM) wave was found to be higher compared to the value at Gunung Baling. Based from geophysical parameters obtained, Gunung Baling survey area was considered as mainly dominated by sediments-filled cavity. Method and results of this study could be useful in solving problems related to subsurface structures in environmental engineering.