Wigner-Ville高阶时频谱及其在塔中奥陶系缝洞型储层预测中的应用

Wigner-Ville higher-order time&frequency spectrum and its application in prediction of Ordovician fractured-vuggy reservoir in Tazhong Area

塔中地区奥陶系深层地震反射信号弱、信噪比低,反射特征复杂,且存在火成岩干扰,造成应用常规属性分析技术不能有效地描述储层特征。Wigner-Ville高阶时频谱分析方法能够准确地反映时变信号的频谱特性,有效压制噪声、提高分辨率。本文结合孔洞地震地质模型,分析了Wigner-Ville高阶时频谱对孔洞储集体地震反射波的敏感性和有效性,并利用该方法对塔中地区奥陶系碳酸盐岩储层进行了预测,证实所求的储层频谱异常与对应的钻遇储层特征相吻合,表明了本文方法的有效性。

There are some problems in exploration of Ordovician depth strata in Tazhong area,such as weak signals,low signal to noise ratio,complicated reflection characteristics,and the interference from the igneous rock,so the routine attribute analysis techniques can not effectively characterize the reservoir characteristics. It was found in the research in this paper that the Wigner-Ville higher-order time & frequency spectrum can effectively reflect the spectrum characteristics and it could suppress the noise,raise resolution and bring objective and accurate result. Based on the void seismic-geological model the sensitiveness and effectiveness of the Wigner-Ville higher-order time & frequency spectrum to void reservoir seismic wave were analyzed,and the technique was used to predict the Ordovician carbonate reservoir. It is proved in the paper that the reservoir spectrum anomalies acquired from the technique match the characteristics of the drilled reservoir,showing the effectiveness of the method.