塔中隆起奥陶系油气性质及运聚富集模式  

Geological characteristics and enrichment model of Ordovician oil and gas in Tazhong Uplift

作　　者：熊昶 王彭[1,2,3] 刘小钰 王伟 赵星星[2,3,4] 孙冲 XIONG Chang;WANG Peng;LIU Xiaoyu;WANGWei;ZHAO Xingxing;SUN Chong(Research Institute of Exploration and Development,PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China;R&D Center for Ultra-Deep Complex Reservoir Exploration and Development,CNPC,Korla 841000,Xinjiang,China;Xinjiang Engineering Research Center for Ultra-deep Complex Reservoir Exploration and Development,Korla 841000,Xinjiang,China;Oil and Gas Field Productivity Construction Division,PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China)

机构地区：[1]中国石油塔里木油田公司勘探开发研究院,新疆库尔勒841000 [2]中国石油天然气集团有限公司超深层复杂油气藏勘探开发技术研发中心,新疆库尔勒841000 [3]新疆维吾尔自治区超深层复杂油气藏勘探开发工程研究中心,新疆库尔勒841000 [4]中国石油塔里木油田公司油气田产能建设事业部,新疆库尔勒841000

出　　处：《岩性油气藏》2025年第1期53-67,共15页Lithologic Reservoirs

基　　金：中国石油天然气集团有限公司科技项目“海相碳酸盐岩油气规模增储上产与勘探开发技术研究”(编号:2023ZZ16YJ04)资助。

摘　　要：以构造、断裂分布、生产动态以及地球化学等资料为基础,对塔中地区奥陶系油气性质与产能分布特征进行了分析,从油气充注、输导体系、构造与油气运聚关系等3个方面对油气富集因素进行了分析,并建立了成藏模式。研究结果表明:①塔中地区奥陶系原油以轻质原油为主,具有低密度、低黏度、低含硫的特征,密度为0.75~0.85 g/m^(3),油气藏气油比为119~82367 m^(3)/m^(3),多相态油气藏并存,且油气相态无明显边界;天然气干燥系数为0.70~0.98,天然气甲烷碳同位素为-35.7‰~-61.4‰,变化范围大;不同区域金刚烷指数(MDI)差异较大,为0.33~0.64;8个主要油气充注点具有原油密度低、气油比高、天然气甲烷同位素及MDI高的特征,沿走滑断裂带向南或远离断裂带方向密度变大,气油比、甲烷碳同位素及MDI均变小,不同区块气侵强度不同造成变化规律存在局部差异。②研究区油气分布格局主要受点状油气充注影响,8个油气充注点周缘油气井通常具有较高的产量,受储层发育规模影响会出现低产井,产能分布具有“北气南油”、“中间气、两边油”及“普遍富气、局部含油”3种类型;远离充注点的低产井及水井大范围分布。③研究区奥陶系油气富集模式为张扭性大断裂控制油气垂向充注,不整合面及走滑断裂控制油气的侧向调整,断裂破碎带叠加层间岩溶为油气聚集提供了储集空间,局部构造高部位及平台区为油气聚集有利指向区。Based on the data of structural analysis,fault distribution,production dynamics,and geochemistry,an analysis is conducted on the characteristics of oil and gas properties as well as productivity distribution in the Tazhong area during the Ordovician period.The factors contributing to oil and gas accumulation are examined from three perspectives:oil and gas charging,transport system,structure,and the relationship between migration and accumulation.Consequently,an accumulation model is established.The results show that:(1)The crude oil found in the Tazhong area during the Ordovician period is predominantly light crude oil with low density,viscosity,and sulfur content.Its density ranges from 0.75 to 0.85 g/m^(3),while the gas-oil ratio varies between 119 and 82,367 m^(3)/m^(3).This region contains multi-phase oil and gas reservoirs where there is no distinct boundary between the oil and gas phases.The dryness coefficient of natural gas ranges from 0.70 to 0.98,and the carbon isotope composition of methane in natural gas shows a wide variation ranging from-35.7‰to-61.4‰.Different regions exhibit amantane index(MDI)values ranging from 0.33 to 0.64.The eight major oil and gas charging points exhibit characteristics such as low crude oil density,high gas-oil ratio,and elevated levels of methane carbon isotope and MDI.Moving along the strike-slip fault zone towards the south or away from it results in an increase in density,while the gas-oil ratio,methane carbon isotope,and MDI all decrease.Variations in gas penetration intensity across different blocks may lead to localized differences in these patterns.(2)The distribution pattern of oil and gas in the study area is primarily influenced by localized oil and gas charging.Oil and gas wells surrounding the 8 charging points typically exhibit high production rates,due to reservoir development scale,there may be occasional occurrences of low-producing wells near the charging points.The regional distribution of filling points'production capacity can be categorized into th

关 键 词：轻质原油 金刚烷指数 张扭性大断裂 走滑断裂 不整合面 断裂破碎带 岩溶作用 奥陶系 塔中隆起 塔里木盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.3[天文地球—矿床学]