强反射轴屏蔽下的致密油薄砂体识别方法研究

Study on Identification Method of Dense Oil Thin Sand Body under the Shield of Strong Reflection Shaft

松辽盆地长垣背斜中浅层低孔、低渗条件下存在的致密油,是目前勘探开发的热点。致密油砂岩被上覆强反射轴的波形干扰屏蔽,无法被常规地震识别出来;厚度小于3m的薄储层,也挑战着地震预测精度的极限。为解决研究区T2(扶余油层顶面)强反射轴下覆致密油薄砂体的识别问题,综合应用子波分解重组、地震沉积学理论、地震属性优选及地质意义分析等方法,较好地解决了该问题,解释精确度较高,说明该方法具有较大的应用潜力。

The tight oil existed in middle shallow layer with low porosity and low permeability in Changyuan anticline of Songliao Basin was the current research focus of exploration and development.The tight oil sandstone was disturbed and shielded by wave of strong reflecting axis,it could not be identified by conventional seismic methods.The thin reservoir with the thickness less than 3m also was the challenge to the limit of seismic prediction accuracy.In order to solve the problem for the identification of tight oil thin sand bodies under T2 strong reflection axis(the top surface of Fuyu Reservoir)in the study area,the methods such as wavelet decomposition and recombination,the theory of seismic sedimentology,seismic attribute optimization and geological significance analysis are synthetically used,by which the problem is solved better,and the interpretation accuracy is higher,it is indicted that these methods have great application potential.