应用吡咯类化合物探讨彩南油田油气运移——以彩南油田东块侏罗系西山窑组油藏为例

INVESTIGATION OF OIL SECONDARY MIGRATIONIN CAINAN OILFIELD USING PYRROLIC NITROGEN COMPOUNDS——A CASE STUDY OF THE JURASSIC XISHANYAO RESERVOIRS IN THE EASTERN DISTRICT OF CAINAN OILFIELD

吡咯类含氮化合物因其结构类型不同而具有明显的运移分馏效应,不失为一种研究油气运移方向的有效手段。彩南油田东区块西山窑组油藏原油属于同一组群类型,吡咯类含氮化合物组成以烷基咔唑为主,苯并咔唑含量低,烷基咔唑中又以C2-咔唑和C3-咔唑为主。对吡咯类运移分馏效应参数的分析表明,彩南油田东区块主要有西方、北方两个原油充注方向,油藏内部断裂对成藏过程起了重要的通道作用。白家海凸起西方的东道海子北凹陷侏罗系煤系地层可能是主要烃源灶,但也不排除凸起南方的阜康凹陷及其北斜坡供烃的可能性。

In recent years,pyrrolic nitrogen compounds were successfully utilized for the research of oil migration ways in the world.Oil samples from reservoir Xishanyao Group in the eastern district of Cainan oilfield are the same oil family, in which pyrrolic compounds are dominated by alkyl-carbazole and C2- ,C3-carbazoles constitute the main parts of alkyl-carbazole. The analyses of parameters for the migration fractionation effects of pyrrolic compounds indicated that there were two oil recharge directions including the north and the west, and the reservoir-inner faults may facilitate oil migration processes. The Jurassic coal-bearing strata in the North Dongdaohaizi Depression which lies to the west of the Baijiahai Uplift are pro-bably the main hydrocarbon source kitchen. Furthermore, an other source kitchen in the Fukang Depression and its north slope which lie to the south of the Baijiahai Uplift is also undeniable.