Interval attenuation estimation from prestack seismic data: A case study from the Arabian Peninsula

Accurately estimated interval attenuation (1/Q) values have several applications, such as in quantitative interpretation and seismic resolution enhancement. Although Q values can be estimated by measuring the spectral ratio between seismic reflections from a target and a reference reflector, the results are influenced by factors such as overburden inhomogeneities. Here, we quantitatively analyze the overburden influence on interval Q estimations using the spectral ratio method, time—space domain prestack Q inversion (PSQI), and τ-p domain PSQI. We compare these three methods using a synthetic dataset and a field dataset acquired onshore the Arabian Peninsula. Synthetic seismic gathers are generated from a three-layer model with a low-Q inclusion in the first layer to mimic overburden inhomogeneity. The field data are preconditioned image gathers from a producing oil field. The synthetic data test shows that the small low-Q body produces a considerable error in estimated Q values. The smallest error (i.e., 13.3%) is in the τ-p domain PSQI result. Theoretically, τ-p domain PSQI could obtain more accurate Q values when there are overburden influences because of the simultaneous inversion scheme and the application in the τ-p domain. The field data application also illustrates that the τ-p domain PSQI produces reasonable interval Q values. Our measured Q values are also comparable with the Q values estimated from hydrocarbon saturated carbonate reservoirs.