准噶尔盆地车排子地区新近系沙湾组层序地层

综合车排子地区新近系沙湾组钻井、测井及地震资料, 将沙湾组划分为二套三级层序。不整合面作为沙湾组的层序界面, 主要从地震剖面和钻井剖面来识别。体系域划分的关键是根据地层上下叠置样式的变化、岩性、测井曲线来确定最大湖泛面的位置。研究区构造为一大型的斜坡, 见不到明显的坡折带, 因此可以建立起无陆架坡折的缓坡盆地层序地层模型。在单一的构造格局控制下,沉积物供应速率、气候和湖平面变化控制了沙湾组层序的发育。结合车89 井、车95 井出油层位的特点, 利用层序地层基本理论, 预测了有利的储盖组合区。

Sequence Stratigraphy of Neogene Shawan Formation in Chepaizi Area,Junggar Basin

According to synthetic core, logging and seismic data from Shawan formation of Neocene in Chepaizi area of Junggar basin, the Shawan formation could be divided into two sequences of Class III. Its unconformity surface as the sequence boundary of Shawan formation can be identified from the seismic profile and well section. The determination of maximum lake flooding surface is based on the changing of stratigraphic superposition pattern, lithology and logging curves, which is the key of the division of systems tract. The study shows that the structure of this area assumes a large-scale slope without distinct slope break, so the sequence stratigraphic model for a basin with gentle slope without continental slope break can be developed. In control of unitary structural framework, the development of Shawan formation should be controlled by the sediment supply rate, the climate and the change of lake level. Also, the favorable reservoir-cap rock assemblages are predicted using sequence stratigraphic theory integrated with oil entry features of Well Che-89 and Che-95.