摘要
塔里木盆地顺托果勒低隆起北部中下奥陶统碳酸盐岩储层中发育多期方解石脉体,对流体活动历史和油气成藏过程都具有重要指示作用.本研究基于对方解石脉体薄片观察、阴极发光、微区原位元素、流体包裹体和锶同位素分析,划分方解石脉体发育期次,确定不同期次方解石脉体成因和形成时间.研究结果表明,顺托果勒低隆起北部碳酸盐岩储层中发育4期方解石脉(C1、C2、C3和C4),不同期次方解石脉的Fe/Mn值和U/Th值均存在一定的差异.C1、C2、C3和C4方解石阴极发光颜色分别为暗红色、不发光-暗蓝色、橙黄色和亮黄色.C1方解石成脉流体来源于深部具有高^(87)Sr/^(86)Sr值流体,C2与C3方解石成脉流体相似,均来源于同地层具有海水性质的成岩流体.C1、C2和C4方解石脉体形成于偏还原环境,C3方解石脉体形成于相对偏氧化环境.通过不同期次脉体中发育的原生盐水包裹体均一温度,结合单井埋藏史和热史确定顺托果勒低隆起北部的C1方解石脉形成于距今约445 Ma,对应于加里东中期Ⅲ幕,C2和C3方解石脉分别形成于距今约430~428 Ma与418 Ma,对应于加里东晚期.
Multiphase calcite veins were developed in the carbonate reservoirs of Middle-Lower Ordovician,which have been an important indicator for both the history of fluid activity and the hydrocarbon accumulation process in the northern Shuntuoguole low-uplift,Tarim basin.Based on the thin section observation,cathodoluminescence,in-situ element analysis,fluid inclusion and strontium isotope analysis of calcite vein,the research divides the phases of calcite vein and determines the origin and formation time of calcite vein in different stages.The results show that there are four phases of calcite vein in the northern Shuntuoguole lowuplift.The Fe/Mn and U/Th values of calcite veins in different periods are different.The cathodoluminescence colors of C1,C2,C3 and C4 calcite are dark red,non-luminous or dark blue,orange yellow and bright yellow,respectively.C1 calcite vein-forming fluid came from deep fluid with high ^(87)Sr/^(86)Sr.C2 and C3 calcite vein-forming fluids are similar and both derived from diagenetic fluids with seawater properties in the same formation.C1,C2,and C4 calcite veins all formed in the partial reduction environment,and C3 calcite veins formed in the partial oxidation environment.Based on the homogenization temperature of the primary aqueous fluid inclusions developed in the veins in different periods,combined with the burial history and thermal history of the single well,it is determined that the C1 calcite vein was formed at about 445 Ma,corresponding to the Middle Caledonian actⅢ,C2 and C3 calcite veins formed at about 430-428 Ma and 418 Ma respectively,corresponding to the Late Caledonian period.
作者
杨毅
王斌
曹自成
黄诚
赵永强
郭小文
罗涛
Yang Yi;Wang Bin;Cao Zicheng;Huang Cheng;Zhao Yongqiang;Guo Xiaowen;Luo Tao(Key Laboratory of Tectonics and Petroleum Resources,Ministry of Education,China University of Geosciences,Wuhan 430074,China;Wuxi Research Institute of Petroleum Geology,SINOPEC,Wuxi 214126,China;Northwest Oil Company Ltd.,SINOPEC,Urumqi 830011,China)
出处
《地球科学》
EI
CAS
CSCD
北大核心
2021年第6期2246-2257,共12页
Earth Science
基金
国家自然科学基金项目(No.41872139).
关键词
方解石脉体
流体包裹体
成脉流体来源
成脉时间
顺托果勒地区
塔里木盆地
石油地质
calcite vein
fluid inclusion
origin of veining fluid
formation time of calcite vein
Shuntuoguole area
Tarim basin
petroleum geology
作者简介
杨毅(1996-),男,硕士研究生,主要从事成岩流体研究.ORCID:0000-0001-6979-628.E-mail:576170139@qq.com;通讯作者:郭小文,E-mail:guoxw@cug.edu.cn。
