川西北蓬溪—盐亭地区下三叠统飞仙关组层序演化及鲕滩展布特征  

Stratigraphic sequence evolution and oolitic shoal distribution of the Lower Triassic Feixianguan Formation in Pengxi-Yanting area,northwestern Sichuan Basin

作　　者：林诚诚 刘宏[1,2,3] 刘冉 徐唱[4] 谭磊 王东 张坤 LIN Chengcheng;LIU Hong;LIU Ran;XU Chang;TAN Lei;WANG Dong;ZHANG Kun(School of Geoscience and Technology,Southwest Petroleum University;Southwest Petroleum University Division of Key Laboratory of Carbonate Reservoirs,CNPC;Sichuan Key Laboratory of Natural Gas Geology;Exploration and Development Research Institute,PetroChina Southwest Oil&Gas Field Company)

机构地区：[1]西南石油大学地球科学与技术学院,四川省成都市610500 [2]中国石油集团碳酸盐岩储层重点实验室西南石油大学研究分室 [3]天然气地质四川省重点实验室 [4]中国石油西南油气田公司勘探开发研究院

出　　处：《海相油气地质》2025年第2期147-156,共10页Marine Origin Petroleum Geology

基　　金：中国石油-西南石油大学创新联合体科技合作项目“深层/超深层碳酸盐岩气田勘探开发基础理论与关键技术研究”(编号:2020CX010000)资助。

摘　　要：基于钻井、测井及三维地震资料,对川西北蓬溪—盐亭地区下三叠统飞仙关组开展层序特征、层序演化与鲕滩发育规律研究。结果表明:①飞仙关组整体可分为3个三级层序(SQ1—SQ3),层序界面具有特征的岩电与地震响应。②SQ1层序具有高角度S形前积反射结构,受高频层序海平面升降旋回控制,发育高频限制型鲕滩沉积,滩体主要沿各期前积体的上部发育,单期滩体规模较小,横向上呈北西向叠置迁移特征。③SQ2层序为低角度前积反射结构,地形坡度整体较缓,受三级海平面升降旋回控制,层序内发育稳定广覆式鲕滩沉积,滩体厚度较大,平面上分布稳定。④SQ3层序为连续平行反射特征,发育局限—蒸发台地相,以泥岩、白云质膏岩互层为特征,厚度均一。该项成果为川西北飞仙关组台内鲕滩油气藏的精细勘探与高效开发提供了地质依据。Abundant oil and gas discoveries have been made in the platform edge oolitic shoals of the Lower Triassic Feixianguan Formation in Sichuan Basin.In order to further promote the research and exploration of the inner platform oolitic shoal,based on drilling,logging,and three-dimension seismic data,the sequence characteristics,sequence evolution and oolitic shoal distribution pattern of the Feixianguan Formation in Pengxi-Yanting area,northwestern Sichuan Basin are studied.The results show that:(1)The Feixianguan Formation can be generally divided into three thirdorder sequences(SQ1,SQ2,SQ3),with typical rock electrical characteristics and seismic response of each sequence boundary.SB1,SB2,and SB3 are all lithological discontinuity surfaces,corresponding to reflection peaks;SB4 is the lithological conversion surface,corresponding to the reflection trough.The four interfaces exhibit abrupt changes in logging responses such as natural gamma and interval transit time.(2)During the deposition period of SQ1 in the study aera,the terrain slope was relatively steep,with a high-angle S-shaped progradational reflection structure.Mainly controlled by the sea-level fluctuation cycle of high-frequency sequences,a high-frequency restricted oolitic shoal sedimentary pattern was developed,in which the deposition scale of a single-stage shoal body was small,and the shoal bodies migrated rapidly in the horizontal direction towards northwest.(3)During the deposition period of the SQ2,the platform depression was basically filled,the overall terrain slope was relatively gentle,and the sequence had a low-angle progradational reflection structure.Controlled by the sea-level fluctuation cycle of third-order sequences,a stable and widely distributed oolitic shoal sedimentary pattern was developed,and the single-stage shoal body had a relatively large thickness and a stable planar distribution.(4)The SQ3 sequence had a continuous parallel reflection structure,and restricted-evaporative platform facies was developed,characterized by interbed

关 键 词：层序 碳酸盐岩 鲕滩 沉积模式 飞仙关组 四川盆地 

分 类 号：TE121.3[石油与天然气工程—油气勘探]