Kirchhoff PSDM angle-gather generation based on the traveltime gradient

Angle-domain common-image gathers from Fresnel volume migration

“…ADCIGs can be extracted from ray-and wave-based migrations in a similar way, since they both characterize angledependent amplitude variations in the imaging domain (Baina et al, 2002). However, ray-based migrations such as KPSDM tend to be more efficient for large-scale 3D data sets and are favorable for migration velocity analysis in anisotropic media (Liu et al, 2015(Liu et al, , 2018. Other studies have also indicated that KPSDM is a better choice for AVA analysis than more sophisticated migration techniques, such as finite-difference migration or reverse-time migration (Ehinger et al, 1996;O'Brien et al, 2019).…”

“…Similar approaches to Xu et al (2001) were proposed by Bleistein and Gray (2002) for a 3D data set, as well as by Brandsberg-Dahl et al (2003), who mainly focused on the implementation of the method for AVA analysis. As an alternative to Xu et al (2001), Liu et al (2015Liu et al ( , 2018 utilized the dynamic programming method (Wang et al, 1999) to calculate traveltimes in 3D transversely isotropic media, followed by ADCIG construction through KPSDM using traveltime gradient fields. Furthermore, Liu et al (2015Liu et al ( , 2018 calculated the scattering opening angles replacing surfacerelated offsets by using the geometric relationship between the source and receiver phase slowness vectors (Audebert et al, 2002;Cheng et al, 2011).…”

“…As an alternative to Xu et al (2001), Liu et al (2015Liu et al ( , 2018 utilized the dynamic programming method (Wang et al, 1999) to calculate traveltimes in 3D transversely isotropic media, followed by ADCIG construction through KPSDM using traveltime gradient fields. Furthermore, Liu et al (2015Liu et al ( , 2018 calculated the scattering opening angles replacing surfacerelated offsets by using the geometric relationship between the source and receiver phase slowness vectors (Audebert et al, 2002;Cheng et al, 2011). Liu et al (2015Liu et al ( , 2018 argued that the constructed ADCIGs are more accurate than those from the ODCIG-to-ADCIG transformation methods and help avoid the complexity that may arise with the common-angle migration proposed by Xu et al (2001).…”

“…Furthermore, Liu et al (2015Liu et al ( , 2018 calculated the scattering opening angles replacing surfacerelated offsets by using the geometric relationship between the source and receiver phase slowness vectors (Audebert et al, 2002;Cheng et al, 2011). Liu et al (2015Liu et al ( , 2018 argued that the constructed ADCIGs are more accurate than those from the ODCIG-to-ADCIG transformation methods and help avoid the complexity that may arise with the common-angle migration proposed by Xu et al (2001).…”