An improved Q estimation approach: the weighted centroid frequency shift method

摘要: Seismic wave propagation in subsurface media suffers from absorption, which can be quantified by the quality factor Q. Accurate estimation of Q is great importance for resolution enhancement seismic data, precise imaging and interpretation, reservoir prediction characterization. The centroid frequency shift method (CFS) currently one most commonly used methods. However, data that contain noise, accuracy stability extracted using CFS depend on choice band. In order to reduce influence band choices obtain with greater precision robustness, we present an improved measurement approach—the weighted (WCFS), incorporates a Gaussian weighting coefficient into calculation procedure conventional CFS. basic idea enhance proportion advantageous frequencies amplitude spectrum weight disadvantageous frequencies. this novel method, first construct Gauss function variance reference wavelet. Then employ it as original signal. Finally, adopted extract factor. Numerical tests noise-free synthetic demonstrate WCFS feasible efficient, produces more accurate results than Tests noisy indicate new has better anti-noise capability application field vertical profile (VSP) further demonstrates its validity5.