# Unveiling Accurate Seismic Imaging through the Advanced Target-Oriented Kirchhoff Migration Method
## 3 Results and Discussions  
The designed workflow was evaluated on two different 2D sections. This was to demonstrate the reliability and the efficiently of the proposed workflow for target-oriented imaging, using seismic redatuming and Kirchhoff migration. Two 2D sections were extracted from SEAM model, a synthetic Gulf of Mexico subsalt data. One section originated from the inline direction, while the other one from crossline. These sections were chosen  
Figure 5: The seismic gather from the observed recorded data between 2 s and 4 s as highlighted in the box is compared with the redatumed data to showcase the efficiency of redatuming method. Seismic redatuming enhances the signal-to-noise ratio in the data, resulting in the redatumed data exhibiting reduced noise and more distinct reflection events. Figure 6: The shot gathers from (**a**) redatumed data and (**b**) modelled data at datum level is compared to validate the accuracy of the redatumed data. The result indicates a strong alignment between the primary reflectors in both datasets as highlighted by yellow arrows. to focus on different geological structures situated below datum level. Figure 7 shows the cross sections of the velocity models used in this study. The original velocity model has been rescaled to expedite computation, with the original size being 10 times larger in x-axis and 16 times larger in z-axis. Firstly, the crossline section model as shown in Figure 7b was used to demonstrate the idea of target-oriented migration through the utilization of redatumed data. Approximately 170 sources and receivers situated on the surface were virtually relocated beneath the salt body at the depth of 380 m, marked by the black dotted line. The interval between each shot and receiver was set at 10 m. Figure 8 shows the retrieved redatumed data. The data showed good signal-to-noise ratio, despite the presence of a block of salt body within the middle of the overburden model. Figure 7: The velocity model is presented in three perspectives: (**a**) top view with dashed line indicate the chosen inline and crossline sections, (**b**) crossline section, and (**c**) inline section. In (**b,c**), the black dotted line signifies the datum level, where the source and receiver are shifted from surface to virtual depth through seismic redatuming. The migration computation occurs below the datum level. Next, we defined our target area below datum level, ranging from 380 m to 600 m in depth. For this region, the travel-time for each source-receiver pair was computed using the velocity model, with consideration given to the isotropic case. Kirchhoff summation was then computed within the defined target area using Equation (2). A comparison was conducted between the migrated image obtained from the full-scale model, the target-oriented migrated image, and the convolutional model. This was carried out to showcase the benefits of the proposed workflow. The outcome is presented in Figure 9, focusing on the specific targeted depth of interest. Referring to Figure 9a, clearly the migrated image has been impacted by the salt body within the overburden. This was evidenced by the presence of strong noise in the image, which, in turn, obscured certain events within the sedimentary layers. A better  
Figure 8: The redatumed shot gathers below datum level of 380 m at different are displayed for various shot locations. These redatumed data have incorporated the effect of the overburden. Figure 9: The comparison between the migrated imaged from (**a**) the full-scale migration using surface recorded data, with a focus on the targeted depth, (**b**) the target-oriented migration utilizing redatumed data, and (**c**) the true reflectivity convolving with the wavelet, focusing on the target depth as the validation model. The results show that the migrated image utilizing redatumed data (**b**) contained high signal-to-noise ratio and effectively imaged the target area without being adversely affected by the salt body in the overburden.