Automatic Gas Pockets Detection by High-resolution Volumetric Q-tomography Using Accurate Frequency Peak Estimation

Conventional imaging does not deal adequately with absorption, especially in the case of strong anomalies. Over recent years, many authors have proposed to compensate the absorption loss effects inside of the migration through the use of an attenuation model. Q tomography has been developed for estimating this attenuation model but is generally limited to estimating attenuation in predefined anomalies. In this paper, we explain how we developed a high-resolution volumetric Q tomography to attain an accurate volumetric estimation of the attenuation model. A key component of our workflow is the estimation of effective attenuation in the pre-stack data domain through accurate picking of the frequency peak. Finally we present a case study where our approach has been used to reveal shallow gas pockets and compensate for absorption in the migration.