CHARACTERIZATION OF UNDERGROUND CAVITIES USING GRAVITY AND GPR METHOD

• Main Author: Ervando Ivan C, Emilianus
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/71900
• Institution: Institut Teknologi Bandung

Detecting underground cavities is an important task that has many advantages on many different fields, such as the safety of construction projects, archaeological excavations, and mineral investigations. Many geophysical methods can be used to determine the location of underground cavities, like gravity, ground penetrating radar (GPR), and seismic. Moreover, two or more geophysical methods can be used at the same time to avoid ambiguities that come from each geophysical method. In this research, the author uses data from gravity and GPR measurement to determine the porosity and water saturation of cavity-filling material of a cylindrical shaped cavity. The equation is derived from bulk density equation and complex refractive index model (CRIM). The equation is then applied to synthetic gravimetry that was obtained using a program written in Python language and synthetic radargram that was obtained using MatGPR. Five different models are used, each with different cavityfilling material, i.e. air, water, dry sand, partially saturated sand, and fully saturated sand. The results have an error value ranging from 0.0801% to 0.3325% for porosity and 0.1115% to 1.4903% for water saturation.