【摘要】 为了搞清松辽盆地嫩江组二三段发育的大型三角洲前积体成因,进行了地震、构造演化和地质综合解释研究,认为大型三角洲前积体是盆地不同构造部位的差异翘倾背景下的产物,在嫩江组二三段沉积时断裂活动趋于静止,由于松辽盆地发生了整体上的翘倾(东部的翘起和西部的沉降),导致盆地古地理格局发生了改变,沉积范围自东向西逐渐减小,沉降中心逐渐向西迁移并收缩,使地层分布和湖区呈现南北延伸的狭长状;物源方向发生了重大改变,由原来的南北向改为东西向,在盆地东部快速抬升的背景下沉积物快速向湖区推进,形成高角度大型进积型三角洲,前积结构明显,前积结构规模大,底超现象明显,但顶超不发育。搞清嫩江组二三段发育的大型前积体的形成机制,对解决嫩江组沉积时期物源方向提供直接依据。更多还原

【Abstract】 In order to clarify the origin of foreset body of delta in the 2-3 members of Nenjiang Formation in the Songliao Basin,the analyses on seismic data,structural evolution and comprehensive geological interpretation were implemented.It was considered that the large foreset body of delta was generated under different tilts in different structural settings,the fault activities tended to be rested during sedimentary period of 2-3 members of Nenjiang Formation,the overall tilt and subsidence occurred in the Songliao Basin——tilting in the east and subsiding in the west,which lead to changes in the paleogeographic pattern of basin.The sedimentary range and subsidence center gradually reduced from east to west,the formation distribution and lake area showed the characters of north-southern strip-shaped extension.The source direction changed from the south-northern to the east-western.The sediments were rapidly carried forward to the lake in the background of eastern part of basin rapidly uplifting.It resulted in the high angle foreset body of delta,which illustrated obvious forset configuration of relatively large extension with obvious baselap and undeveloped toplap.It could provide a direct evidence of source direction of the period of Nenjiang Formation clarify the generation mechanism of Depression-lacustrine large delta of 2-3 member of Nenjiang Formation.It is helpful for the evaluation of oil and gas exploration in Songliao Basin and provides a guidance for the evaluation of residual resources exploration and deployment.更多还原