层序地层级次对生物碎屑灰岩沉积演化的控制作用——以中东X油田Mishrif组中下段为例  

Controlling effects of sequence stratigraphic orders on sedimentary evolution of bioclastic limestone:a case study of middle-lower section of Mishrif Formation in the Middle East X Oilfield

作　　者：余义常 郭睿[2] 李峰峰 林敏捷 沈博珩 沈毅 韩海英[2] 宋世琦 YU Yichang;GUO Rui;LI Fengfeng;LIN Minjie;SHEN Boheng;SHEN Yi;HAN Haiying;SONG Shiqi(China National Oil and Gas Exploration and Development Company Ltd;PetroChina Research Institute of Petroleum Exploration&Development;Geological Exploration and Development Research Institute,CNPC Chuanqing Drilling Engineering Company Ltd)

机构地区：[1]中国石油国际勘探开发有限公司 [2]中国石油勘探开发研究院 [3]中国石油集团川庆钻探工程有限公司地质勘探开发研究院

出　　处：《海相油气地质》2024年第1期57-70,共14页Marine Origin Petroleum Geology

基　　金：国家科技重大专项下属课题“伊拉克大型生物碎屑灰岩油藏注水开发关键技术研究与应用”(编号:2017ZX05030-001);中国石油天然气股份有限公司科技重大专项“中东大型生物碎屑灰岩油藏地质特征及评价技术”(编号:2017D-4406)联合资助。

摘　　要：以中东X油田Mishrif组中下段为例,综合利用地震、测井、岩心、铸体薄片及常规物性等资料,开展层序地层级次识别及层序地层级次对沉积演化的控制作用研究。结果表明:(1)Mishrif组发育5个三级层序和10个四级层序,中下段MB2—MC1层段对应三级层序SQ2—SQ3,包括4个四级层序,其内部发育11个五级层序和多个六级层序。(2)研究区发育次盆地碳酸盐开阔台地-弱镶边台地沉积,储层主要发育于台内滩和台缘滩中,按照生物碎屑类型可将滩相进一步细分为5种类型。(3)六级层序控制单滩体的沉积序列,五级层序控制多滩体的组合特征,四级层序决定沉积微相演化特征,三级层序决定沉积体系的演化特征。(4)SQ2层序的PSS3、PSS4四级层序早期为斜坡环境,发育透镜状滑塌粗粒沉积,后期发育台地边缘滩间→中能滩相沉积序列;SQ3层序的PSS5、PSS6四级层序发育台地边缘滩间→中能滩相→高能滩相沉积序列。SQ3沉积结束后形成了特殊的下切谷充填沉积。Based on the data of seismic,well logging,core,cast thin sections and conventional physical properties,taking the middle-lower section of Mishrif Formation in the Middle East X Oilfield as an example,the identification of sequence stratigraphic orders and the controlling effects of sequence stratigraphic orders on sedimentary evolution are studied.The results show that:(1) The Mishrif Formation is divided into5third-order sequences(SQ1-SQ5) and 10 fourth-order sequences(PSS1-PSS10).The MB2—MC1single layers in the middle-lower section of Mishrif Formation correspond to SQ2-SQ3,including4fourth-order sequences(PSS3-PSS6),in which multiple fifth-order and sixth-order sequences are developed.(2) Carbonate open platform-weakly rimmed platform of a sub-basin is developed in the study area,and the reservoirs mainly exist in platform margin shoals and open platform shoals.The shoal facies can be further subdivided into rudist shoal,rudist-containing bioclastic shoal,bioclastic-arene shoal,bioclastic-spherical shoal and bioclastic shoal according to bioclastic types.(3) The sixth-order sequence controls the sedimentary sequence of a single shoal body,the fifth-order controls the combination characteristics of multiple shoal bodies,the fourth-order sequence determines the evolution characteristics of sedimentary microfacies,and the third-order sequence determines the evolution characteristics of sedimentary systems.(4) In the early stage of PSS3and PSS4 of SQ2sequence,the two fourth-order sequences are in a platform front slope environment,with the development of lens-shaped collapsed coarse-grained sediments.In the later stage of PSS3and PSS4,a sedimentary sequence of the platform margin intershoal→medium energy shoal is developed.The PSS5and PSS6of the SQ3sequence develop a sedimentary sequence of platform margin intershoal→medium energy shoal→high energy shoal.After the completion of SQ3sedimentation,a special incision filling sedimentation is formed.

关 键 词：生物碎屑灰岩 层序地层级次 沉积演化 Mishrif组 中东 

分 类 号：TE121.34[石油与天然气工程—油气勘探]