西加拿大沉积盆地Simonette区块上泥盆统Duvernay页岩地质特征与流体分布规律  

Geological characteristics and fluid distribution of the Upper Devonian Duvernay shale in Simonette block in the Western Canada Sedimentary Basin

作　　者：孔祥文[1] 汪萍[1] 夏朝辉[1] 张晓玲 曲良超[1] 郭泽坤 Kong Xiangwen;Wang Ping;Xia Zhaohui;Zhang Xiaoling;Qu Liangchao;Guo Zekun(PetroChina Research Institute of Petroleum Exploration&Development)

机构地区：[1]中国石油勘探开发研究院,100083

出　　处：《中国石油勘探》2022年第2期93-107,共15页China Petroleum Exploration

基　　金：国家科技重大专项“海外重点探区目标评价与未来领域选区选带研究”(2016ZX05029-005);中国石油天然气集团有限公司重大科技专项“海外油气田开发关键技术研究与应用”(2019D-4412);中国石油天然气股份有限公司科技专项“海外气田开发关键技术研究”(2021DJ3303)。

摘　　要：Duvernay页岩是西加拿大沉积盆地最重要的一套页岩油气富集与生产层系。该页岩是一套最大海侵期形成的富含沥青质暗色页岩,与国内页岩气藏相比,Duvernay页岩气藏的突出特点是富含凝析油,且凝析油含量平面差异大,流体分布复杂。通过对西加拿大沉积盆地中国石油Simonette区块上泥盆统Duvernay页岩构造和沉积演化、地层、地球化学、储层特征和流体分布规律的分析和解剖,提出了富含液烃页岩气勘探开发策略。研究结果表明:(1)Simonette区块Duvernay页岩上页岩段储层厚度大、层内不发育碳酸盐岩隔夹层、TOC高、储层物性好,是主力勘探开发目的层;(2)Simonette区块Duvernay页岩镜质组反射率(R_(o))为1.1%~1.6%,位于富含液烃条带,根据气油比可划分为挥发性油、特高含凝析油和高含凝析油3个区带,随着凝析油含量的增加,甲烷含量逐渐降低,原油密度逐渐增大,原油采收率逐渐减小;(3)勘探开发策略上,平面上应优先评价和开发易动用、采出程度高的特高含凝析油区带和高含凝析油区带,再开发挥发性油区带,纵向上以上页岩段高TOC层为主要目标。Duvernay shale is the most important shale series for oil and gas enrichment and production in the Western Canada Sedimentary Basin.It is a set of asphaltene rich dark shale formed during the maximum transgression period.Different from the domestic shale oil and gas reservoirs,Duvernay shale gas reservoir is characterized by high condensate content,great variation in condensate to gas ratio on the plane,and complex fluid distribution.The tectonic and sedimentary evolution,stratigraphy,geochemistry,reservoir characteristics,and fluid distribution of the Upper Devonian Duvernay shale in Simonette block in the Western Canada Sedimentary Basin are analyzed,and the exploration and development strategy of liquid-rich shale is proposed.The study results show that:(1)The upper part of Duvernay shale in Simonette block has large reservoir thickness,no carbonate interlayers,high TOC content,and good reservoir physical properties,which is the main exploration and development target layer;(2)Duvernay shale in Simonette block is located in a liquid-rich zone,with vitrinite reflectance(R_(o))between 1.1%-1.6%,which is divided into three zones based on the condensate to gas ratio,namely the volatile oil zone,ultra-high gas condensate content zone and high gas condensate content zone.As the condensate-to-gas ratio(CGR)increases,the methane content gradually decreases,the crude oil density gradually increases,and the oil recovery factor gradually decreases;(3)In terms of exploration and development strategies,priority should be given to evaluation and development of ultra-high gas condensate content and high gas condensate content zones which are easier to be produced and have a high degree of producing rate,and followed by the volatile oil zone.Vertically,the high TOC shale layers are focused as the main targets.

关 键 词：西加拿大沉积盆地 Duvernay页岩 地质特征 流体分布 

分 类 号：TE111.1[石油与天然气工程—油气勘探]