渤海海域凹陷区油气控藏规律与勘探实践——以渤中西洼为例

Hydrocarbon accumulation law and exploration practice in the sag areas of Bohai Sea: a case study on west subsag of Bozhong Sag

李龙 薛永安 张新涛 王国强 魏国财 徐春强

LI Long XUE Yong'an ZHANG Xintao WANG Guoqiang WEI Guocai XU Chunqiang

中海石油(中国)有限公司天津分公司

Tianjin Branch of China National Offshore Oil Co., Ltd., Tianjin 300459, China

为明确渤中西洼凹陷区新近系油气控藏规律，在渤中西洼油气勘探成果及成藏特点整体解剖的基础上，重点分析古隆起的大小、断层和泥岩盖层的发育程度对新近系油气平面运聚和空间分布的控制作用，提出“隆-断-盖”联控成藏模式。研究结果表明，古隆起控制油气汇聚部位，断层的发育程度控制新近系油气富集层位，泥岩盖层的厚度制约馆陶组油气富集。古隆起、断裂、泥岩盖层的有效配置共同决定了凹陷区具备形成大规模油气藏的条件。在此成藏规律指导下，钻探了渤中13A和龙口7A构造，均取得了成功，进一步证实了“隆-断-盖”控藏模式在凹陷区勘探中的可行性，对深化凹陷区油气成藏认识和下一步寻找有利勘探目标都具有重要意义。

In order to figure out the hydrocarbon accumulation laws of the Neogene in west subsag of Bozhong Sag, the oil and gas exploration achievements and the hydrocarbon accumulation characteristics in this area were analyzed comprehensively.Then, the joint controlling effect of the size of paleo-uplift and the development degree of fault and mudstone caprock on the areal migration & accumulation and spatial distribution of Neogene oil and gas reservoirs were mainly dissected.And accordingly, it was for the first time to propose the hydrocarbon accumulation pattern of "uplift-fault-caprock" joint control.It is indicated that the paleo-uplift controls the hydrocarbon accumulation location, the development degree of fault dominates the hydrocarbon enrichment horizon in the Neogene, and the thickness of mudstone caprock restricts the hydrocarbon enrichment of Guantao Formation.Obviously, the effective configuration relationship of paleo-uplift, fault and mudstone caprock determines the favorable conditions for the formation of large-scale oil and gas reservoir in the sag area.Under the guidance of this hydrocarbon accumulation pattern, a series of drilling are carried out in Bozhong13A and Longkou 7A structures and they are commercially successful.It is further verified that the hydrocarbon accumulation pattern of "uplift-fault-caprock" joint control is feasible to the exploration in sag areas.The research results are of great significance to deeply understand the hydrocarbon accumulation in sag areas and search for favorable exploration targets further.

10.13639/j.odpt.2018.S0.002