【摘要】 地震波在含油气储层传播时会发生较强的能量衰减和速度频散,以特定的频散属性定量地表征速度频散程度,并可将其作为一种新的烃类指示因子用于储层预测。基于介质界面反射系数随频率变化的数学关系,本文研究了频变振幅随炮检距的变化规律;应用贝叶斯反演理论,可从分频叠前道集中反演出表征纵波速度频散程度和频散程度随炮检距变化的梯度等属性参数。模型测试结果验证了本文所述方法的可行性及频散属性识别油气的有效性,实际应用则进一步说明据此反演得到的频散属性可为储层烃类检测提供较可靠的数据支撑,有效地降低了烃类检测的多解性。更多还原

【Abstract】 The anomalously high attenuation of seismic wave can occur in hydrocarbon reservoirs,which is associated with velocity dispersion.Therefore,the level of the velocity dispersion can be characterized by dispersion attribute which can be used as a new hydrocarbon indicator in hydrocarbon detection.Based on the mathematical relation between the reflection coefficient and frequencies,we construct the forward model of frequency-dependent amplitude variation with offsets.Using the Bayesian inversion theory,the dispersion dependent attribute indicating the dispersion level and gradient is estimated from frequency-dependent prestack seismic gather.The model test shows the feasibility and the validation of this method.The real data application illustrates that this method provides us a new way and diminishes the ambiguity in the hydrocarbon detection.更多还原