# Unveiling Accurate Seismic Imaging through the Advanced Target-Oriented Kirchhoff Migration Method
## 1 Introduction
Despite that, it is recognized as the optimal approach for pre-stack migration and continues to be utilized to date, particularly within the framework of least-squares migration [18; 19; 20; 21; 22]. The continued relevance of Kirchhoff migration stems from its algorithmic flexibility. First, it allows Kirchhoff migration to accommodate diverse acquisition geometries and source-receiver configurations. This adaptability makes it well suited for processing various types of seismic data, including land, marine, and borehole data. Secondly, Kirchhoff migration also offers flexibility in defining the imaging conditions. Through modification of the weighting functions employed in the migration process [23; 24], it becomes feasible to amplify specific features or attenuate undesired artifacts. Thirdly, owing to its flexible and expedient algorithmic benefits, the Kirchhoff migration method is capable of achieving target-oriented migration [25]. The most straightforward approach involves its direct application in amplitude summation by focusing solely on the hydrocarbon reservoir areas. Nevertheless, this method exhibits reduced accuracy, as it fails to consider the influence of the overburden during the migration process  
In fact, the hydrocarbon reservoirs or areas of interest are typically located at greater depths within the subsurface, and the recorded data tend to be distorted during the wave propagation through the overburden, particularly in the presence of complex anomalies such as salt or shallow gas clouds. These distortions are due to the strong lateral variation of the velocity in the overburden which then results in strong scattering effects, dispersion, internal multiples, and mode conversion as well as anelastic losses [26]. This is precisely why the Kirchhoff migration approach is typically avoided in the presence of complex geology, as it tends to introduce artifacts in the images, thereby disrupting the interpretation beneath the complex overburden. The distortions are observed as diffractions, discontinuities, or undulations in the seismic record; thus, neglecting these effects may leads to inaccurate analysis for hydrocarbon reservoir imaging or characterization. Therewith, seismic redatuming is used to simplify the recorded data and eliminate the overburden effects [26; 27] by virtually relocating the acquisition surface beneath the complex geology, simulating the acquisition as if it were conducted at the redatumed level [28]. A seismic redatuming method was primarily used as a straightforward static correction, mainly applied on land seismic data, However, it has emerged as part of subsurface imaging to addressed challenges associated with the complex near surface conditions. The advantages of seismic redatuming have been increasingly acknowledged for achieving enhanced imaging and velocity model building compared to standard data processing [29]. Even with the existence of various redatuming methods, such as Wavefield Redatuming [30; 31; 32], and Marchenko redatuming [33; 34; 35; 36], the fundamental principle remains consistent: dividing the subsurface into two distinct zones--the overburden and the target area. Then, the correction of transmission effects within the overburden is accomplished by employing a specific redatuming method to derive redatumed data. Recent literature highlights the extensive utilization of seismic redatuming advantages in the context of target-oriented velocity model building. Recognizing that the velocity model building process is exceedingly time-consuming within seismic processing and imaging procedures, seismic redatuming is employed to effectively decrease the overall time required for generating precise velocity models. For example, it has found applications in time-lapse Full Waveform Inversion [37; 38], datum-based Full Waveform Inversion [39; 40], and target-oriented elastic Full Waveform Inversion [41; 42; 43].