四川盆地德阳—安岳裂陷西侧大探1井震旦系灯影组天然气勘探重大突破及意义  

Well Datan 1 in west side of Deyang-Anyue rift,Sichuan Basin:Great breakthrough in natural gas exploration in Sinian Dengying Formation and its significance

作　　者：文龙[1] 谢继容[1] 张本健[2] 赵容容[3] 王文之[2] 周刚[2] 武鲁亚 汪华[2] 马奎 WEN Long;XIE Jirong;ZHANG Benjian;ZHOA Rongrong;WANG Wenzhi;ZHOU Gang;WU Luya;WANG Hua;MA Kui(PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China;Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China;Exploration Division,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610056,China)

机构地区：[1]中国石油西南油气田公司 [2]中国石油西南油气田公司勘探开发研究院 [3]中国石油西南油气田公司勘探事业部

出　　处：《天然气工业》2023年第11期7-18,I0001,共13页Natural Gas Industry

基　　金：中国石油天然气股份有限公司重大科技专项项目“海相碳酸盐岩油气规模增储上产与勘探开发技术研究”(编号:2023ZZ16YJ01)。

摘　　要：近期,部署实施于四川盆地德阳—安岳裂陷西侧(以下简称裂陷西侧)的风险探井大探1井,在震旦系灯影组二段、灯影组四段(以下简称灯二段、灯四段)分别测试获天然气42×10^(4)m^(3)/d、81×10^(4)m^(3)/d,取得了裂陷西侧天然气勘探的重大战略突破。为了评价裂陷西侧灯影组沉积、储层和油气成藏地质条件,通过对野外露头、岩心、薄片及测试资料等进行分析,重新厘定了区内老井地层、沉积格局、有利区带展布特征,深化了裂陷西侧灯影组油气成藏地质认识,指导了下一步天然气勘探。研究结果表明:①裂陷西侧震旦系地层完整、序列齐全,灯影组地层广泛分布,灯四段与麦地坪组呈整合接触,桐湾Ⅱ幕位于麦地坪组顶部,因此灯影组未遭受到广泛剥蚀;②裂陷西侧灯二段、灯四段丘滩体面积分别约为3000 km^(2)、4000 km^(2),丘滩相储层特征与裂陷东侧基本一致,储集岩均以凝块白云岩和砂屑白云岩为主,差异主要体现在西侧灯影组渗透性更高,并发育大量晚期网状缝,此与该区受晚期强烈挤压密切相关;③川西南地区发育中元古界峨边群、震旦系陡山沱组、寒武系筇竹寺组3套烃源岩,受晚期构造挤压,通源断裂发育,3套烃源岩与灯影组形成下生上储、侧生旁储、上生下储高效天然气成藏组合;④大探1井所在的大兴场构造具备双层构造体系特征,保存条件好,而且关键成藏期位于古构造高部位,早期普遍成藏,晚期调整定型,具备规模成藏的含油气地质条件;⑤提出了非继承性构造演化区,在正向地质单元寻找规模化的滩带,在负向地质单元寻找烃源岩的勘探思路,并建立了“滩带—断层—烃源”跨时空配置成藏新模式。结论认为,大探1井在裂陷西侧灯影组天然气勘探取得的重大突破,进一步展示了该区巨大的天然气勘探潜力,且该区有可能成为继安岳气田之后一个重要的天然气�Recently,Well Datan 1 drilled in the west side of Deyang-Anyue rift of the Sichuan Basin(hereinafter referred to as"west side"for short)obtains natural gas from the second and the fourth Member of Sinian Dengying Formation(hereinafter referred to as"Deng 2 Member"and"Deng 4 Member"for short)at the rate of 42×10^(4) m^(3)/d and 81×10^(4) m^(3)/d respectively,marking a significant strategic breakthrough in natural gas exploration in the west side.In order to evaluate the sedimentary,reservoir and hydrocarbon accumulation geological conditions of the Dengying Formation in the west side,this paper analyzes the field outcrops,cores,thin sections and test data.Based on this,the stratigraphy,sedimentary patterns,and distribution characteristics of favorable zones in the old wells of the study area are redetermined,and the geological conditions for the hydrocarbon accumulation in the Dengying Formation of the west side are understood further,which provides guidance for the next exploration.And the following research results are obtained.First,in the west side,the Sinian is complete in stratigraphy and sequence,the Dengying Formation is widely distributed,Deng 4 Member is in conformable contact with the Maidiping Formation,and the Tongwan Ⅱ episode is located at the top of Maidiping Formation,indicating that the Dengying Formation has not undergone extensive denudation.Second,the mound beaches of Deng 2 and Deng 4 Members in the west side cover an area about 3000 km^(2) and 4000 km^(2),respectively,and their reservoir characteristics are basically consistent with those in the east side,with reservoir rocks being dominated by clotted dolomite and doloarenite.Their differences are embodied mainly as higher permeability and abundant developed late network fractures in the west side,which is closely related to the late strong compression in this area.Third,three sets of source rocks are developed in the southwestern Sichuan Basin,i.e.,the Middle Proterozoic Ebian Group,the Sinian Doushantuo Formation and the Cambrian Qion

关 键 词：四川盆地 德阳—安岳裂陷西侧 大探1井 灯影组 台缘带 成藏组合 勘探重大突破 

分 类 号：P618.13[天文地球—矿床学]