Joint Migration Inversion including Q effects: towards Q estimation

Abstract

Summary Seismic waves that travel through the Earth’s subsurface encounter various attenuation effects that can alter their shape, strength, and energy over time. These effects include geometric spreading, reflection, transmission, and dispersion. To obtain high-resolution information on the sub-surface, it is essential to account for all these attenuation effects. The Full Wavefield Migration (FWM) and Joint Migration Inversion (JMI) methods utilize the Full Wavefield Modeling (FWMod) scheme, which incorporates geometric spreading, reflectivity, and transmission effects, as well as multiple scattering. The FWMod process is designed in a modular manner, where wavefield operators describe propagation and reflection/transmission. Therefore, integrating the quality (Q) factor impact is relatively straightforward by redefining the propagator. The primary objective of this study is to include a spatially varying Q-factor impact in both FWMod and JMI via a predefined velocity-Q relation. It was demonstrated that JMI cam account for these values during the inversion process. In addition, it is demonstrated that the JMI method is sensitive enough to distinguish inversion results from correct or wrongly assumed Q-models.