On the gradient calculation in 1.5-dimensional joint migration inversion

Abstract

The traditional joint migration inversion (JMI) technology faces the amplitude-versus-offset (AVO) challenge, which has been demonstrated before. We now apply JMI to 1.5-dimensional (1.5D) media, and use a velocity model and a density model to parameterize its solution space. As physically correct one-way propagation, reflection and transmission operators can be analytically formulated in 1.5D JMI, the AVO challenge is thus resolved. In this paper, we derive the complete theory behind the gradient calculation in 1.5D JMI, and further use a 1.5D synthetic example to demonstrate its correctness. This work is an important component of the 1.5D JMI theory, which will have applications in (locally) horizontally layered media containing strong multiple generators.