敦煌盆地中、下侏罗统含油气系统分析

敦煌盆地油气勘探能否取得突破取决于盆地中源岩的生烃潜能和圈闭的有效性．运用含油气系统研究思路，结合野外露头观察和盆地充填序列特征的分析。对盆地侏罗系含油气系统的地质要素(源岩、储集岩、盖层及上覆岩层)和作用过程(可能生成的油气运移、聚集、圈闭)进行定性评价和综合解释，结合露头岩样的有机地化分析和露头剖面的油气地质解释，推测出该盆地西端南部中、下侏罗统的暗色泥岩和含煤岩系中的炭质页岩为主要的烃源岩，而其间的不整合面上的砂岩层为主要的储集体和主要的油气勘探目的层系．

Analysis of Middle-Lower Jurassic Petroleum System in Dunhuang Basin

Source rock potential and trap efficiency determine the success of petroleum exploration in the Dunhuang basin,Gansu Province, China. According to the integrated analysis of surface section and sedimentary sequences, the authors analyze the geological elements (source rocks, reservoir, sealing and overlaid rocks) and processes (migration, accumulation and trapping) of the Middle and Lower Jurassic petroleum system in the Dunhuang basin. The results indicate that the Middle and Lower Jurassic dark mudstones and carbonous shales in coal-bearing measures have been inferred to be the main source rocks in the southwestern basin, there is a possibility of using petroleum system theory in the exploration of the Dunhuang basin, Gansu Province in China, and the sandstones lying above the unconformities may be taken as the main targets for hydrocarbon exploration.