柴达木盆地北缘马北Ⅰ号圈闭油气成藏机理与模式

在马北Ⅰ号圈闭形成史、油源、油气充注及输导体系特征分析的基础上，指出N。晚期—-N2早期，尕丘凹陷中侏罗统烃源岩生成的原油运移到马北Ⅰ号圈闭马北1井浅层（〈1000m）和马北Ⅲ号圈闭。N2中期，赛什腾凹陷中较高成熟度的中侏罗统烃源岩排烃，油气运移到马北Ⅰ号圈闭马北1井深层（〉1000m）。喜马拉雅运动晚期使马海凸起整体抬升，圈闭定型，油藏埋藏较浅。马北Ⅰ号圈闭成藏模式可归纳为：燕山运动期基岩古隆起上形成披覆构造，圈闭继承性发育，晚期定型；双源两期成藏。

Mechanism and Model of Hydrocarbon Accumulation in Mabei-I Trap in Northern Margin of Qaidam Basin

The evolution history,oil source,filling time and carrier system in Babei-I trap of northern margin of Qaidam basin are analyzed.It is indicated that from Late N1 to Early N2,oil generated from Middle Jurassic hydrocarbon source rocks in Gaqiu sag migrated to the shallow layer(<1 000 m) of Well Mabei-1 within Mabei-I trap and Mabei-III trap.In the period of Middle N2,the source rocks with higher maturity of Middle Jurassic in Saishiteng sag originated expulsion of hydrocarbon followed by migrating into the deep layer(>1 000 m) of Well Mabei-1.In the Late Himalayan movement,the whole Mahai swell was uplifted,featuring fixed traps and shallower reservoirs.The model of hydrocarbon accumulation in Mabei-I trap could be described as that the drape-like structure was formed on the paleo-uplift of basement in the period of Yanshan movement,the traps were evolved successively and formed by the end of Yanshan period.Also,there exist two-source and two-stage hydrocarbon accumulations in this area.