Based on magnetic susceptibility and density contrast models, the final purpose of analyzing potential field data is to estimate the parameters of the sought source, such as depth, structural index, horizontal location, and physical characteristics. Meanwhile, when conducting geophysical explorations, it is critical to ascertain the exact depth of the underground source as accurately as possible. In this study, the potential field is interpreted using the depth from extreme points “DEXP” automatic transformation technique, founded on the accurate processing of the local wavenumber at various scales and the extreme points of the DEXP field to extract the depth, horizontal position and structural index of the source. This highly stable method demonstrates low sensitivity to noise-contaminated data since it employs an upward continuation filter and a potential field derivative operator. In addition, the findings are more dependable than those of alternative techniques. Furthermore, the procedure is entirely automatic and does not require any basic information from the data collection area. In other words, DEXP can be considered a fast imaging method. Since multiscale methods are less reliant on the magnetic induction field, nowadays, they are utilized more frequently in magnetic field computations. At the beginning of this research, synthetic scenarios are simulated, and then the depth extension of the postulated models was demonstrated by implementing the DEXP technique to the synthetic gravity and magnetic data. Subsequently, this method has been implemented on data from the Ghareh-Aghaj potash exploratory area in Zanjan Province, North of Iran. By summarizing this method's results, it can be seen that the potash mass exhibits a minimal transverse expansion and has extended more in the depth dimension. Compared to the findings obtained via exploratory boreholes, these findings demonstrate a level of agreement that can be considered satisfactory.