Correlation of Residual Anomaly and Isoseismal Map by Using Power Spectral Density Method in Palu City Region

This research was conducted to see the correlation between residual anomaly map, geological map, and isoseismal map and how they contribute to the determination of earthquake-prone areas. Moreover, the area studied is an area that is difficult to obtain geophysical data such as urban areas. The residual anomaly is obtained by calculating the bouguer anomaly from elevation data and free-air correction satellite, which then through the FFT process changes the spatial domain to the frequency domain in MATLAB. Thus, it can separate regional anomaly maps with residuals. Using the overlaying technique on two maps, namely residual anomaly maps with isoseismal, a clear correlation was found between the residual anomaly value and the impact of the earthquake as well as the validation of the geological map in the area.