Second Vertical Derivative Using 3-D Gravity Data for Fault Structure Interpretation

Abstract

Derivative calculation of potential field for signal enhancement is common to be applied in order to provide geologic interpretation. Second Vertical Derivative (SVD) can be used to estimate fault structure and also tends to emphasize shallower geologic anomalies. In this work, we evaluate SVD results using 2-D and 3-D gravity data from two synthetic models (combination of two faults at different depth). Horizontal grid stations designed in the flat surface with 100 m interval for 2-D synthetic data calculation, while 3-D synthetic data calculation designed with addition of 50 and 100 cm in vertical levels (above each surface grid stations). Comparison SVD calculation using 2-D and 3-D synthetic gravity data conducted to perform the possibility of combined gradient interpretation proceedure. SVD from real data aplication identify 2 normal fault with (NE-SW trend) and 1 reverse fault (with NW-SE trend).