论文详情
松辽盆地三肇凹陷扶余油层以浅水三角洲沉积体系为主,单层砂体厚度薄,横向变化快,受T2界面强反射层屏蔽作用影响,目的层砂体无明显地震反射特征。如何降低强屏蔽层的调谐影响,突出薄砂体并进行精细刻画,一直是困扰本区勘探开发的技术难题。研究发现强屏蔽现象主要与反射系数的干涉作用有关,地震波是反射系数干涉作用形成的,当地层中存在较大反射系数时,由于地震波主频较低,会突出强阻抗界面的影响,弱反射系数被淹没,解决强屏蔽效应问题主要应减少地震波干涉效应的影响。由于提高分辨率处理手段局限性较大,经研究分析及试验,采用地震波形指示反演技术,即利用地震波形的横向变化信息代替传统变差函数,实现高频成分的井震联合反演,降低地震强阻抗界面的影响,有效解决了研究区强屏蔽下的薄储层预测问题。
Fuyu oil layer in Sanzhao Depression,Songliao Basin developed typical sedimental system of shallow water delta that had thin layer of sandbody and fast transverse change.There is no obvious seismic reflection characteristics which affected by the shield effect from strong T2 reflection.How to reduce the strong shield tuning effect,highlight the responses from the fuyu oil layer thin sandbodies and has a fine description,it’s always been a problem in exploration and development in the target.Strong impedance shielding phenomenon is mainly associated with the tuning effect of strong reflection coefficient in the study.When the reflection coefficient is high in the formation,it causes the low seismic frequency.Thus the low reflection coefficient will be "swamped",and the influence of the strong impedance interface will be highlighted.Therefore,the main consideration of weakening shielding effect should be given to reduce the influence of the seismic wave interference effect.Due to the limitations of increased resolution by seismic processing,through a large number of trials,we adopted a new high-resolution inversion technology that called seismic meme inversion.It makes full use of lateral seismic waveform space change information instead of conventional variogram,and realizes seismic and well joint characterization of high frequency components.It effectively reduces the influence of strong seismic impedance interface and achieves the high precision thin reservoir prediction under strong shielding effect in the target area.
国家科技重大专项(2011ZX05013-001)与CNPC重大科技专项“陆上地震勘探关键装备和软件研发”(2013E-3808)联合资助。