垦东北地区古近系油气输导体系特征

Characteristics of the Paleocene Oil and Gas Transmission System in North Kengdong Area

针对垦东北地区古近系油气输导体系特征及其对油气分布的控制作用不明确等问题,基于地质、地震、测井等资料,分析输导要素的发育特征,并对输导能力及组合类型进行了评价和划分,明确输导体系与油气分布的关系。研究表明:成藏期活动性较强的油源断层与侧向连通砂体或不整合输导层是油气输导的重要通道;断层-砂体/不整合侧向分流系数大于下限值时,油气可沿断层向砂体/不整合输导层侧向充注。根据输导要素组合特征和输导能力划分出5类输导体系,其中Ⅰ、Ⅱ、Ⅲ型输导能力强,Ⅳ、Ⅴ型输导能力弱,造成现今垦东北地区中部多层系富集,东部、西部深层聚集的油气分布特征。该研究成果对垦东北地区下一步油气勘探工作具有一定参考意义。

To address the problems such as the characteristics of the Paleocene oil and gas transmission system and its control role on oil and gas distribution in north Kendong Area,based on geological,seismic and well-logging data,we analyzed the development characteristics of the transmission elements and evaluated and classified their transmission capacity and combination types,so as to clarify the relationship between the transmission system and the oil and gas distribution.The study shows that oil source faults with strong activity during the reservoir formation period and laterally connected sand body or unconformable carrier bed are important channels for oil and gas transmission;when the fault-sand body/unconformable lateral flow coefficient is greater than the lower-limit value,the oil/gas may be laterally charged along the faults to the sand body/unconformable carrier bed.Five transmission systems have been classified according to the characteristics of the combination of transmission elements and transmission capacity,of which typeⅠ,typeⅡ,typeⅢhave strong transmission capacity,and typeⅣ,typeⅤhave weak transmission capacity,resulting in the multilayered system was enriched in the middle of the north Kendong Area,and the oil and gas were deeply gathered in the east and west.The study results have certain reference significance for the next oil and gas exploration work in north Kendong Area.