川中地区雷三^(2)亚段“灰质岩类”储层主控因素及有利区预测  

Influential factors and prospects on calcareous reservoirs of Lei_(3)^(2) submember,central Sichuan Basin

作　　者：张豪 辛勇光 徐唱 任纪博 田瀚 潘柯宇[3] ZHANG Hao;XIN Yongguang;XU Chang;REN Jibo;TIAN Han;PAN Keyu(PetroChina Hangzhou Research Institute of Geology,Hangzhou,Zhejiang 310023,China;Sichuan Basin Research Center,PetroChina Research Institute of Petroleum Exploration and Development,Chengdu,Sichuan 610041,China;Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China)

机构地区：[1]中国石油杭州地质研究院,浙江省杭州市310023 [2]中国石油勘探开发研究院四川盆地研究中心 [3]中国石油西南油气田公司勘探开发研究院

出　　处：《天然气勘探与开发》2023年第4期123-132,共10页Natural Gas Exploration and Development

基　　金：中国石油天然气集团有限公司上游领域基础性前瞻性项目“残留型海相盆地构造-岩相古地理重建技术研究”(编号:2021DJ0501)、“海相碳酸盐岩有效储层形成与保持机理及分布预测研究”(编号:2021DJ0503)

摘　　要：四川盆地中部三叠系中统雷口坡组随着勘探的深入,在蒸发台地潟湖相碳酸盐岩储层获得重要突破,揭示了雷三^(2)亚段勘探新层系,展示了良好的勘探前景。针对雷三^(2)亚段灰质岩类储层主控因素及分布不清的问题,通过岩心、岩屑分析化验和薄片观察,结合井震分析等手段,明确了川中地区雷三^(2)亚段灰质岩类储层主控因素及有利区分布。研究结果表明,①川中地区雷三^(2)亚段储层岩性以泥质石灰岩和灰质泥岩为主,主要发育纳米—微米级无机孔、有机孔和微裂缝;②黏土矿物高和含石膏时储层孔隙度较高,裂缝能有效改善储层渗透性;③应用膏盐岩厚度划分雷三^(2)亚段地震相,应用嘉四段—嘉五段厚度预测揉皱变形区,二者叠合区西充—营山地区为灰质岩类储层有利发育区,面积4000 km2;④灰质岩类储层能够形成自生自储、膏盐岩封堵、大面积分布的非常规油气藏,是下一步四川盆地雷口坡组油气勘探的现实领域。An important breakthrough has been made in carbonate reservoirs of evaporate-platform lagoon facies through the exploration on the Middle Triassic Leikoupo Formation in central Sichuan Basin,which reveals a new prospective target,namely the second submember of the third member of Leikoupo Formation(Lei_(3)^(2) submember).So,through core and cuttings analysis,thin-section observation,and well-to-seismic analysis,the main influential factors and prospects were figured out for calcareous reservoirs of this submember in central basin.Results show that(i)these Lei_(3)^(2) reservoirs are mainly composed of argillaceous limestone and limy mudstone developed with nano-to micron-sized inorganic pores,organic pores and microfractures;(ii)there is high porosity in some reservoirs with rich clay mineral or coexistence with gypsum,and the permeability is improved by fractures with effect;(iii)for this submember,the seismic facies were divided by using the thickness of gypsum-salt rock,and the crumple deformation zone was predicted by the thickness from Jialingjiang 4 to Jialingjiang 5 members.With an area of 4,000 km2,Xichong-Yingshan area featuring the overlap of aforementioned seismic facies and deformation zone is a favorable belt to develop with calcareous reservoirs;and(iv)the calcareous reservoirs can form massive self-generating and self-preserving unconventional reservoirs with gypsum-salt rock as the seal,and they will certainly be the realistic domain for oil and gas exploration in the Leikoupo Formation of Sichuan Basin.

关 键 词：四川盆地中部 潟湖相 雷三^(2)亚段 灰质岩类储层 储层主控因素 自生自储 地震相 

分 类 号：P618.13[天文地球—矿床学]