Interval Q estimation and a quality indicator -- QQI
Chuandong (Richard) Xu, Robert R. Stewart
We use the spectral ratio method with zero-offset VSP data to develop a new approach to calculate the continuous interval QP value in Ross Lake area. A Q estimation Quality Indicator (QQI) for getting a stable Q has been established. This QQI curve also explains why sometimes we cannot get good results. Due to the much narrower frequency bandwidth of S-wave, QS estimation is not as good as QP.