【摘要】 品质因子Q是表征地下介质对地震波吸收衰减特性的参量,在储层预测和油藏描述中有着重要的应用。频率域属性组合法利用地震波谱的统计属性(质心频率和惯心频率)组合估算Q值,具有较高的理论精度,但估算结果依赖波谱的提取质量。为避免地震波谱的提取,提出时间域属性组合法,根据时间域子波信息直接估算频率属性:对于常相位子波,其频谱质心频率等于包络峰值处的瞬时频率,惯心频率等于质心频率乘以子波导数包络峰值处的瞬时频率。当地震子波近似常相位时,可在时间域提取其质心频率和惯心频率,实现Q值的估算。模型和资料测试结果表明,时间域属性组合法估算Q值具有一定的可信度和可行性。更多还原

【Abstract】 Quality factor Qis a parameter that describes wave attenuation characteristics in subsurface media,and it plays an important role in reservoir prediction and characterization.Frequency statistics attributes(mass centroid frequency and inertia frequency)in frequency domain is usually used to estimate Q.This method has theoretically high accuracy,but the estimates rely on spectrum extraction quality.To avoid seismic spectrum extraction,we propose in this paper a combination approach in time domain.The approach estimates directly frequency attributes from wavelets in time domain.For the constant phase wavelet,its mass centroid frequency is equal to the instantaneous frequency at the envelope peak,and its inertia frequency is equal to the instantaneous frequency at envelope peak of mass centroid frequency multiplied by the derivative of the wavelet.For a wavelet with an approximate constant phase,the mass centroid frequency and the inertia frequency can be directly extracted and the Qvalues can be estimated.Test results on model and real data show that estimating Qvalue by the proposed combination approach has credibility and viability.更多还原