Estimation of quality factors from CMP records

Estimates of the quality, Q, factor are commonly obtained from vertical seismic data or stacked surface seismic data. This paper describes a method that allows Q‐factor to be estimated directly from common midpoint (CMP) gathers. Absorption of the wavefield is dependent on three parameters: frequency, traveltime in the medium, and medium Q‐factor. Assuming that the amplitude spectrum of the seismic source signature may be modeled by that of a Ricker wavelet, we derive an analytical relation between Q‐factor and seismic data peak frequency variation both along offset and vertical time direction. The Q‐factor is estimated from CMP gathers using a layer‐stripping approach.