The enhancement techniques of potential field data are commonly used to detect the boundary locations of geological structures. There are many different techniques for estimating the source boundaries. Through synthetic examples and Bouguer data from the southern Red Sea, we have evaluated the performance of 15 enhancement techniques. The findings show that the tilt angle of horizontal gradient (TAHG) and fast sigmoid (FSED) techniques perform better than other techniques under almost all scenarios. Moreover, these two techniques can avoid producing false structures or connected structures as other techniques. The extracted lineaments from the TAHG and FSED were compared with surface faults of the study area. As a result, major differences are caused by rifting effect on the oceanic crust. The obtained results provide valuable information to better understand the structural features of the southern Red Sea and to introduce a more reliable structural interpretation.

Edge enhancement techniques have been widely used in mapping geologic features, such as faults, contacts and dikes. The universal disadvantages of previously presented filters are that they cannot balance signals caused by geological structures located at different depths or they bring false edges or the images obtained from these filters have low resolution. We introduce a filter SF that uses the softsign function and derivatives of the horizontal gradient to solve these problems. The applicability of the filter is exemplified with three synthetic data sets and aeromagnetic data from the Olympic Peninsula, northwestern United States. Compared to other edge detector methods, the filter is able to outline the source edges more precisely and clearly, and there are no spurious lateral boundaries in the output results.

Saudi Arabia covers most of the Arabian Peninsula and is characterized by tectonic regimes ranging from Precambrian to Recent. Using gravity data to produce the lateral boundaries of subsurface density bodies, and edge detection of potential field data, a new subsurface structural map was created to decipher the structural framework controls on the distribution of gold deposits in Saudi Arabia. Moreover, we detected the relationships between major structures and mineral accumulations, thereby simultaneously solving the problem of edge detectors over complex tectonic patterns for both deeper and shallower origins. Analytic signal (ASg), theta map (TM), TDX, and softsign function (SF) filters were applied to gravity data of Saudi Arabia. The results unveil low connectivity along the Najd fault system (NFS) with depth, except perhaps for the central zones along each segment. The central zones are the location of significant gold mineralization, i.e., Fawarah, Gariat Avala, Hamdah, and Ghadarah. Moreover, major fault zones parallel to the Red Sea extend northward from the south, and their connectivity increases with depth and controls numerous gold mines, i.e., Jadmah, Wadi Bidah, Mamilah, and Wadi Leif. These fault zones intersect the NFS in the Midyan Terrane at the northern part of the AS, and their conjugation is suggested to be favorable for gold mineralization. The SF maps revealed the boundary between the Arabian Shield and Arabian Shelf, which comprises major shear zones, implying that most known mineralization sites are linked to post-accretionary structures and are not limited to the Najd fault system (NFS).