海相油气地质2025，Vol.30Issue(3)：193-205,13.DOI:10.3969/j.issn.1672-9854.2025.03.001
塔北西部上寒武统白云岩储层特征及主控因素
Characteristics and main controlling factors of dolomite reservoir of Upper Cambrian:a case study of the Xiaoerblak section,western Tabei Uplift
摘要
Abstract
Taking the Cambrian Xiaoerblak section in the Keping outcrop area as an example,this study aim to clarify the differences in the characteristics and distribution patterns of dolomite reservoirs of the Upper Cambrian Xiaqiulitage Formation in the western Tarim Basin.Based on a systematic analysis of rock thin section,carbon and oxygen isotope compositions,and U-Pb dating,the conclusions are drawn as follows:(1)The Xiaqiulitage Formation,with a total thickness of 350 m,is divided into six members,and is composed of grain dolomite,thrombolite dolomite,stromatolite dolomite,and laminated microbialite dolomite.Seven lithofacies association and two third-order sequences are identified in the Xiaqiulitage Formation,reflecting the overall transition of tidal flat subfacies to inner platform shoal subfacies from bottom to top.(2)The reservoir spaces are dominated by matrix dissolution pores,vugs(dissolution cavities),and intergranular fractures within breccias.The columnar stromatolitic dolomite and thrombolitic dolomite exhibit the best physical properties,followed by grain dolomite,with the overall characteristics of moderate-to-high porosity and moderate-to-low permeability.A comprehensive evaluation indicates that the reservoir properties are optimal in Member 1,Member 2,and Member 6,while Member 5 ranks slightly lower.(3)The dolomite was formed during the early diagenetic stage,and reservoir development is primarily controlled by the combined effects of sedimentary microfacies,unconformity surfaces,and high-frequency sequences.The reservoirs can be classified into two types:unconformity-karst dolomite reservoirs and inner mound-shoal dolomite reservoirs.This research provides critical support for evaluating favorable exploration zones in the Cambrian dolomite plays of the western Tabei area,and offers reliable evidence for hydrocarbon reservoir assessment,particularly in the Xiongying region.关键词
白云岩储层/主控因素/下丘里塔格组/肖尔布拉克剖面/塔里木盆地Key words
dolomite reservoirs/main controlling factors/Xiaqiulitage Formation/Xiaoerblak section/Tarim Basin分类
石油、天然气工程引用本文复制引用
呼焕,郑剑锋,罗新生,段军茂,吕奇奇,石磊,田浩男..塔北西部上寒武统白云岩储层特征及主控因素[J].海相油气地质,2025,30(3):193-205,13.基金项目
本文受中国石油基础性前瞻性重大科技专项课题"叠合盆地中下组合规模储层形成机制与分布规律研究"(编号:2023ZZ02)、中国石油重大科技专项课题"碳酸盐岩油气富集规律及有利区带研究"(编号:2023ZZ16YJ01)联合资助 （编号:2023ZZ02）
