论文部分内容阅读
万安盆地勘探程度较低,运用PetroMod软件,对其烃源岩成熟史进行了模拟。盆地模拟结果表明:盆地内发育3套烃源岩,其中西卫群、万安组为主力烃源岩,李准组为次要烃源岩,生烃门限深度在3 400 m左右,3套烃源岩分别在18,10和7 Ma进入生烃门限,西卫群和万安组烃源岩现今绝大部分已处于高成熟—过成熟阶段,以生气为主,而李准组烃源岩现今处于低—中成熟阶段,以生油为主。万安盆地中部坳陷为盆地内最大的富烃和生烃坳陷,热演化程度高于其他构造单元,沟通烃源岩与储层的深大断裂对油气运移起重要的输导作用,新近系油气成藏的关键时期为早上新世,且新近系储层总体上以气藏为主。
Wan’an Basin has a low exploration level. The PetroMod software was used to simulate the maturity history of source rocks. The basin simulation results show that there are three sets of source rocks developed in the basin, of which the Xeiwei Group and Wan’an Formation are the major source rocks, and the Lizhun Formation is the secondary source rock with a hydrocarbon generation threshold depth of about 3 400 m and three sets The hydrocarbon source rocks entered the hydrocarbon generation thresholds at 18, 10 and 7 Ma respectively. Most of the source rocks of the Xuanwei Group and Wan’an Formation are now in the high mature-maturity stage and are mainly gas-generating, while the Lizhun Formation hydrocarbon source Rock is now in the low-maturity stage, with oil-based. The central depression in Wan’an Basin is the largest hydrocarbon-rich and hydrocarbon-generating depression in the basin, with a higher degree of thermal evolution than other tectonic units. The deep faults that communicate source rocks and reservoirs play an important guiding role in hydrocarbon migration. The critical period of hydrocarbon accumulation in Neogene is Early Pliocene, and the Neogene reservoirs are mainly gas reservoirs.