Abstract: The oil area of the Jurassic System in Central Sichuan is regarded as poor mine because no breakthroughs were made in exploration of the area in the past five decades. The main reservoirs are the early confirmed shell limestone of 1st and 3rd interval of Da’anzhai Section (with the porosity being less than 1%). They are identified as fractured oil fields with the geological resources amounting to 11×108t. Later, the reservoirs of muddy shell limestone were found in the area (with the porosity being 1.56%). With the exploration potential boosted, the resources in the area rose to 35×108t. The present study indicates that the average porosity of source strata – 2nd interval of Da’anzhai Section mud shale subzone – is 2.35% while the average porosity of mud shale containing organic matter is 3.8%. Oil and gas were found in drilling. They are the main reservoirs in the area with many high-yield wells drilled. Therefore, the Jurassic System in Central Sichuan is regarded as locally sourced and accumulated shale oilfields. In the semi-deep lacustrine zone of 26000 square kilometers in Central Sichuan, the thickness of mud shale is higher than 40 meters while TOC is 1.5-2%. It is the favorable zone for exploration of shale oil. Based on the volumetric method, the geological resources of shale oil from Jurassic Da’anzhai Section and Lianggaoshan Formation are 164×108t. It is proposed that source strata of Jurassic mud shale should be further studied, establishing an experiment zone of shale oil development in Central Sichuan. Da’anzhai Section of Gongshanmiao and Guihua oilfields as well as Lianggaoshan Formation of Nanchong Structure can be selected for pilot development of shale oil, accelerating the exploration process in this field.

Key words: Central Sichuan, Jurassic System, Da&rsquo, anzhai Section, Lianggaoshan Formation, shale oil field, geological resources, technological production, exploration targets

摘要： 川中侏罗系油区50 多年来勘探没有重大突破，被认为是贫矿。最早确认大安寨段大一亚段、大三亚段介 壳灰岩（孔隙度小于1%）是主要储层，定为裂缝性油田，地质资源量仅为11×108t；后发现含泥质介壳灰岩储层（孔 隙度为1.56%），扩大了勘探潜力，资源量增至35×108t。目前研究发现，烃源层大二亚段泥页岩平均孔隙度为2.35%， 含有机质泥页岩平均孔隙度为3.8%，钻井中油气显示很好，有不少高产井，为主要储层，据此认为川中侏罗系是源生 源储的页岩油田。川中26000km2 半深水湖相区，泥页岩厚度大于40m，TOC 含量为1.5% ～ 2%，是页岩油勘探有利区。 以容积法估算川中侏罗系大安寨、凉高山两段页岩油地质资源量为164×108t。建议对侏罗系泥页岩烃源层含油气情况 进一步深入研究；开辟川中页岩油开发试验区，选择公山庙、桂花油田大安寨段，南充构造凉高山组页岩油进行先导 开发试验，加快该领域探索进程。

关键词: 川中, 侏罗系, 大安寨段, 凉高山组, 页岩油田, 地质资源量, 技术开采量, 勘探目标