Paper Summary

A frequency domain tomographic inversion was developed to estimate frequency dependent energy attenuation by using prestack depth migration common image gathers (CIGs). The frequency dependent attenuation is estimated from the centroid frequency difference for reflections in CIGs. Migration stretch and ghost effects are taken into account to get correct measurements of frequency. This method makes correction for these factors to obtain correct frequency difference, utilizes the actual ray paths and avoids using amplitude information. It is relatively insensitive to some of amplitude loss factors, such as geometric spreading, reflection and transmission loss, source and receiver radiation patterns. Q tomography was used to derive the Q model for karst media. The compensation of amplitude loss improves the sub-karst amplitude fidelity.