分频解释技术在碳酸盐岩储层预测中应用

APPLICATION OF SEPARATE FREQUENCY INTERPRETATION TECHNIQUE IN PREDICTION OF CARBONATE RESERVOIR

常规频谱地层检测技术分辨率有限,采用分频解释技术能够排除时间域内不同频率成分的相互干扰,可以得到高于传统分辨率的解释结果,获得更精细的地质图像。缝洞型碳酸盐岩储层预测是研究工区油气勘探需要解决的难题。研究工区主要目的层为奧陶系碳酸盐岩储层,非均质性强,横向变化快,而地震资料主频和信噪比都较低,用常规方法难以描述碳酸盐岩储层分布。针对研究工区碳酸盐岩储层特点,首先用模型验证了分频解释技术能够揭示储层横向之间由于岩性、物性等因素引起的微小振幅变化,最大限度地提高地震资料的解释分辨率,并利用该技术,结合三维可视化技术和钻井资料,对某区碳酸盐岩储层进行了预测。预测结果与实钻数据相一致,由此可见,分频解释技术可以刻画碳酸盐岩储层空间展布特征,碳酸盐岩储层分频属性在三维空间的响应特征是高调谐振幅。

Separate frequency interpretation technique can eliminate mutual interference of different frequency in time-domain,and obtain interpretation results with higher resolution comparing with the former data.Reservoir Prediction in Fractured reservoirs is difficult in exploration research of oil&gas.The target formation in study area is Ordovician carbonate reservoir.Its anisotropies are strong,change laterally is fast and its dominant frequency and Signal-to-Noise ratio is low.The description of reservoirs using the conventional method is very difficult.In this article,the authors verify the Separate frequency interpretation technique can reveal the seismic amplitude's little changes form lithology and physical property along the reservoir direction with model analyses,make a prediction using it and 3D visualization,and good results that is the same as the data of real drilling is achieved.Therefore,the spectral decomposition can improve effect of carbonate reservoir prediction.The Separate frequency attribute's response characteristics of carbonate reservoir is high amplitude in 3-D space.