准噶尔盆地车排子地区新村油田石炭系构造特征与成藏条件

通过对准噶尔盆地车排子地区新村油田石炭系构造特征、储层、油气分布特征、主要油藏类型及其成藏条件的研究,建立了该区成藏综合模式。结果表明,研究区总体上处于构造斜坡带,具有北高南低、西高东低、南北分块的构造特征,地层产状平缓;研究区在石炭纪处于区域拉张构造应力背景,并在拉张应力作用下形成以北东—南西向展布为主的拉张型断裂组合样式;研究区大部分地区地层等高线平直,不利于形成背斜构造圈闭,但各级断裂发育,为形成断层遮挡圈闭提供了有利条件,同时也可作为油气运移的通道。依据石炭系断裂分布、断裂模式及其组合,将研究区的断裂划分为复合地垒系统、复合地堑系统和零星断裂系统。控制研究区油气运聚成藏的主要地质因素是断裂、裂缝及岩性变化或物性封堵。

A study of Carboniferous structure characteristics and reservoir-forming conditions in the Xincun Oilfield, Chepaizi area, Junggar Basin

Through the analysis of Carboniferous structure characteristics, distribution characteristics of reservoir bed and hydrocarbon, major oil pool styles and reservoir-forming conditions in the Xincun oilfield in Chepaizi area of Junggar Basin, a synthetic hydrocarbon accumulation model was established. The results show that the study area is located on a tectonic slope on the whole, which has the tectonic characteristics of higher in the north and lower in the south, higher in the west and lower in the east, and south-north partitioning with gentle stratigraphic attitude. The study area mainly developed tensional faults in Carboniferous, which are in NE-SW direction and were formed in a regional tensional tectonic stress background. In the study area, the strata contour lines are mainly flat-straight, suggesting that the strata could not provide favorable conditions for the formation of anticline traps, but the study area has well-developed multi-order faults, which could provide favorable conditions for the formation of faulted block traps and pathways for oil-gas migration. Carboniferous faults can be divided into composite horst system, composite graben system and sporadic fault system based on their distribution, patterns and assemblies. The major geological factors controlling oil-gas migration and accumulation in the Xincun oilfield are the faults, fractures and lithologic changes or physical sealing.