## 4 Results and Discussion
### Gravimetric Analysis
Faults F1 to F8 were typically oriented NE-SW, parallel to the Atlantic margin, whereas the other three faults (P9, F10, and F11) were generally perpendicular to this margin. Overlaying all the structures on the residual gravity map determined their positions based on the positive and negative anomalies (as depicted in Figure 7b). This highlighted the crucial role of these structures, particularly the major faults, in shaping the Precambrian bedrock of the Ifni inlier. These faults are likely responsible for the undulations of the bedrock topography beneath the Paleozoic cover, which could account for the observed anomalies. Figure 7: (**a**) Maxima of the THG map of the Ifni inlier; (**b**) Superimposition of the interpreted structures from the THG maxima to the residual anomaly map: (1) Interpreted major gravity fault; (2) Interpreted minor gravity fault. In addition, we applied the Tilt angle filter to the residual anomaly map as a secondary method for detecting gravity contacts. Zero contours typically indicate these contacts, represented by the white dashed line. This contour coincided with most of the faults identified by the THG technique, supporting their presence as structural characteristics of the study area (see Figure 8a). Moreover, we utilized the Euler deconvolution technique on the gravity data to further characterize the geological structures based on their rooting depth. We computed solutions corresponding to fault-like structures with a structural index (SI) of zero, a maximum relative error (T) of 15%, and a moving window size (W) of 10 \(\times\) 10. These solutions are presented in Figure 8b, together with the faults identified by the THG method. Upon examining this figure, we observed that the most closely clustered solutions are located along the detected faults. Thus, the Euler deconvolution not only confirmed the existence of the faults identified by the THG method but also provided additional information regarding their depth. The new faults, inferred from the gravity data, were superimposed on the Ifni nilier's structural map (refer to Figure 9), resulting in an updated map. After a more thorough analysis of this updated map, it was found that some of the interpreted structures had not been included in the original geological map. However, some of the new structures corroborated the existence of previously observed faults, partially or entirely coinciding with them. These findings indicate that the current study has contributed to a more thorough characterization of the deep structure of the Ifni nilier by providing valuable insights into the fault system that impacts this Precambrian section of the Anti-Atlas range. Figure 8: (**a**) Structures interpreted from the THG map of the Ifni nilier overlaid to the Tilt derivative map: (1) Interpreted major gravity fault; (2) Interpreted minor gravity fault; (**b**) Superimposition of the same structures to the Euler solutions was calculated using a structural index SI = 0, a moving window of 10 \(\times\) 10, and a maximum relative error of 15%. Additionally, the newly identified faults may represent concealed structures buried beneath recent sedimentary deposits and harboring high-potential groundwater that may have remained undetected by surface geological observations. The rose diagrams established separately for the observed faults and those inferred from gravity data show that the study area is affected by a network of faults of different orientations. The observed faults are organized along a range of directions varying from NNW-SSE to E-W with a predominance of N-S and ENE-WSW orientations (Figure 9b). However, the direction of the faults interpreted from the gravity data is dominated by the NE-SW trend (Figure 9c). This difference in the shape shown by the two rose diagrams is explained by the fact that the observed faults include a large number of minor accidents of low horizontal extension that mainly affect the Paleozoic cover and whose slip does not allow the contact of blocks with a significant density contrast.