平衡剖面技术在榆东地区构造演化分析中的应用

Application of balanced-profile technology in the tectonic evolution analysis of Yudong area

利用TSM软件,结合平衡剖面技术,对榆东地区东西向的两条地震剖面进行了平衡剖面恢复,编制了各剖面的构造演化史图。研究结果表明,榆东地区扶杨油层自泉头组开始沉积,至嫩江组末期基本定型,期间共经历了四期演化阶段,即泉三段—泉四段的稳定下沉阶段,青山口组—姚一段的强烈伸展阶段,姚二、三段的稳定下沉阶段和嫩江组末期的构造反转阶段。通过对比各剖面的伸展量和伸展速率的变化特征,发现研究区总体的变形呈现南强北弱、东强西弱的特点,其中在青山口组沉积期的平均伸展速率较大,为37 m/Ma,与区域上松辽盆地在该时期内强烈伸展的坳陷背景相吻合。

By using TSM software together with balanced-profile technology,this paper made balanced-profile recovery of the two east-west seismic profiles and compiled the tectonic evolution history of each profile.Research results indicated that Fuyang oil layer in Yudong area began to deposit in Quantou period and nearly formed in the end of Nenjiang period.It experienced four tec tonic evolution stages,including stable subsidence stage of K1q3-K1q4,intensive extension stage of K2q-K2y1,stable subsidence stage of K2y2-K2y3 and tectonic reversion stage of late K2n.Through comparing the changes of amounts and rates of extensions among each profile,it was found that the deformation of strata in the south and east is greater than that in the north and west respec tively.The average extension speed of Qingshankou deposit period was high up to 37 m/Ma,matching with the strongly extensive depression background of Songliao basin in the same period of the area.