AVO技术在苏里格气田SQW区块的应用

SQW区块与苏里格气田总体构造特征相似,主要表现为地层平缓,构造圈闭不发育,以岩性气藏为主。由于区内各类岩石速度和密度等参数相互接近,应用传统的波阻抗反演方法难以识别盒8段气层,因此本文选用基于泊松比分析的AVO技术进行储层预测。参考Verm等提出的基于泊松比反射率的AVO技术,在区内利用岩石物理分析建立NI-PR彩色标定图板,通过彩色交会图解释技术分析实际地震道集AVO反演的NI和PR属性,可以获得较准确的含气储层空间展布信息。AVO储层预测结果与研究区内各井盒8段实际情况吻合率达80.5%。

AVO applications in the Block SQW of Sulige Gas Field

The tectonic features in the Block SQW are entirely consistent with the other areas of Sulige Gas Field.There the formations are gentle,structure traps are not developed,and stratigraphic gas reservoirs are developed.Since parameters such as velocity and density of different rocks are very close,the traditional impedance inversion is difficult to identify gas strata in He8.So AVO based on Poisson's ratio is selected in our research,which was proposed by Verm and Hilterman.The original two-dimensional color NI-PR crossplot analysis method can essentially improve the ability to distinguish 3 types of classic AVO anomalies.And this analysis can be applied to seismic anomalies identification.With petrophyscial analysis and the AVO forward modeling in the research area,we get the NI-PR color calibration crossplot and summarized the response characteristics of AVO anomalies.Using color crossplot interpretation to analyze attributes NI and PR,reliable spatial distribution of gas reservoirs is obtained.80.5% of the reservoir prediction results are well matched with the actual drilling data.