油气成藏过程对低对比度油层形成的控制作用

低对比度油层的识别是目前油气勘探开发中急需解决的重要问题之一,而解决其成因是识别低对比度油层的基础和关键所在。以松辽盆地南部大情字井油田青二段为例,重点研究了油气成藏过程在此类油层形成中的控制作用。松辽盆地南部大情字井油田青二段为典型低孔—低渗储层,油气运移的阻力相对较大,圈闭构造幅度较小,因而油气成藏动力相对不足。油气成藏过程中成藏动力不足、多期成藏和成藏后受构造活动改造等原因导致油水关系复杂,这对低对比度油层的形成具有重要的控制作用。

Control of Hydrocarbon Migration and Accumulation Processes in the Low-Contrast Reservoir

It is known that the recognition of a low-contrast reservoir is the key problem in oilfield exploration and development. Based on previous researches, this paper focuses on the control of hydrocarbon migration and accumulation processes in the formation of low-contrast reservoirs. The Qing-2 member of Qingshankou Formation, Daqingzijing Oilfield in southern Songliao Basin typically belongs to the type of the low porosity and the extremly low permeability. Relatively large migration resistance and small amplitude of structure must have led to a relative shortage of formation dynamics. The main factors of complex oil-water relation which can cause low-contrast reservoir are relative to the shortage of forming dynamic, multi-stage hydrocarbon accumulation and regional tectonic activities.