内蒙古天草凹陷油气生成的盆地数值模拟及油气资源远景分析

利用BASIMS盆地模拟系统对银根-额济纳旗盆地天草凹陷白垩系烃源岩的油气生成进行了模拟研究。模拟结果表明,白垩系烃源岩的油气生成过程经历了早白垩世早中期初步生排烃阶段,早白垩世中晚期大规模生排烃阶段和晚白垩世以来生排烃停滞阶段3个时期,全区累计生烃1836 80Mt,下白垩统巴音戈壁组烃源岩是天草凹陷的主力烃源岩层系,其生排烃量占总量的90%。用聚集系数法计算的天草凹陷的总资源量为0 74×108t,在同规模、同等勘探程度的油气勘探新区中是很有资源远景的地区之一。

Numeric Basin Modeling and the Prospect of Petroleum Resources of Tiancao Depression

Based on BASIMS basin modeling system, the hydrocarbon generation of the Cretaceous source rock in the Tiancao depression, Yingen_Ejinaqibasin was simulated. The simulated results show that hydrocarbon generation of the Cretaceous source rock involves three stages including primary generation period in the early and middle Early Cretaceous stage,large scale generation stage in the middle and late Early Cretaceous stage and the generation stagnant period since the Late Cretaceous.The total amount of hydrocarbon generated in geological history is 1836\^80 million tons,90% of which were generated by Bayingebi formation source rock of the Lower Cretaceous. The total quantity of oil and gas sources is 74 million ton, which is assessed by accumulation coefficient method. This indicates that the Tiancao depression is one of the areas with source prospect.