南鄱阳凹陷油气系统分析与勘探选区评价

Analysis of Petroleum System and Assessment of Prospect Areas in Southern Poyang Sag

综合分析了南鄱阳凹陷生储盖等基本油气地质条件,选取有代表性的地震解释剖面、钻井剖面,建立64个一维虚拟点,以盆地模拟为手段,按照动态、正演方式,进行了油气系统研究。依据油气聚集区—主力烃源岩—主要储层—主要成藏期(可靠级别)的系统命名原则,认为南鄱阳凹陷存在P_1、P_2—P、K_3—K_3～E(潜在的)再生烃油气系统,并对系统中的油气生成、运聚、保持、破坏过程进行了阐述,辅以相应的油气显示佐证,并分别计算了印支期、燕山期、喜马拉雅期的生烃量。在油气系统研究的基础上,结合已钻探井的失利原因分析,进行了勘探选区评价。

Through a discussion on the basic hydrocarbon geological conditions,such as source rocks,reservoirs,cap and so on, in Southern Poyang Sag,sixty-four 1-D imaginary points were built up from the representative seismic profiles and drilled sections.In the light of the quasi-3D basin modeling which em- phasizes dynamics and forward simulation,petroleum system was analyzed and set up for the sag.By the nomenclature of petroleum system,i.e.the'Hydrocarbon accumulative area —Chief source rock—Chief reservoir—Important pool formation stage (a reliability grade)',it is of opinion that there is a re- generated'P_1-P_2—P-K_2-K_3-E (potential)'petroleum system in Southern Poyang Sag.The processes of hydrocarbon gener- ation,migration,accumulation,conservation and destruction, which were confirmed by the hydrocarbon indicators,are re- presented.And the oil/gas-generating amount during Indosini- an,Yenshanian and Himalayan periods was calculated.The potential prospecting areas were assessed according to the analyzed petroleum system and drill fail results.