Determining fault structure using first horizontal derivative (FHD) and horizontal vertical diagonal maxima (HVDM) method: A comparative study

Fault is an important parameter in both hydrocarbon and geothermal exploration. It could be able as a secondary permeability that controlee and improve fluid flow within a reservoir. Fault zone is usually related to high permeability zone as well as indicated by any high-density contrast. There is a relatively new HVDM method that could be applied to determine and indicate a subsurface normal or reverse fault. This study is comparing the method with the conventional ones, the FHD method. Both methods are principally working based on the existing of lateral density contrast of gravity data. The FHD value is obtained from root sum square of horizontal X first derivative and horizontal Y first derivative of gravity data, meanwhile the HVDM value is obtained by horizontal, vertical and diagonal coefficient root sum square of 2-Dimensional DWT. The comparison of both, FHD and HVDM, methods are applied toward synthetic model and real gravity data. Identification of fault structure on FHD and HVDM are shown by maximum value. Based on the result of synthetic model gravity data, the FHD could determine fault structure in a better way than HVDM whereas on gravity real data FHD and HVDM have a slightly similar response. As we do not have supported proven geology and geophysical data, the study could not verify and justify yet the real gravity data.