鄂尔多斯盆地西部奥陶系克里摩里组有效储层发育控制因素  

Controlling factors for effective reservoir development of Ordovician Kelimoli Formation in western Ordos Basin

作　　者：李慧敏 赵振宇[3] 宋微[3] 张涛[4] 赵当妮 蒋婷婷 张丽 陈朝兵 LI Huimin;ZHAO Zhenyu;SONG Wei;ZHANG Tao;ZHAO Dangni;JIANG Tingting;ZHANG Li;CHEN Zhaobing(School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi’an,Shaanxi 710065,China;Research Institute of Petroleum Exploration and Development,PetroChina,Beijing 100083,China;No.2 Gas Production Plant,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi 710200,China)

机构地区：[1]西安石油大学地球科学与工程学院,西安710065 [2]陕西省油气成藏地质学重点实验室,西安710065 [3]中国石油勘探开发研究院,北京100083 [4]中国石油长庆油田分公司第二采气厂,西安710200

出　　处：《石油实验地质》2023年第3期434-442,共9页Petroleum Geology & Experiment

基　　金：国家自然科学基金(41802140);国家科技重大专项(2016ZX05050006);陕西省自然科学研究基础计划项目(2019JQ-257);刘宝珺地学科学基金(DMSM2019007);西安石油大学研究生创新与实践能力培养计划(YCS22213066)联合资助。

摘　　要：近年来,鄂尔多斯盆地西部奥陶系的天然气勘探取得了一定进展,其中以奥陶系克里摩里组天然气聚集程度最高,但其有效储层发育控制因素复杂,导致勘探效果不理想。基于岩心观察、薄片鉴定、钻录井等资料,系统研究了克里摩里组有效储层发育类型及控制因素,建立了有效储层发育模式。鄂尔多斯盆地西部克里摩里组有效储层类型主要有白云岩晶间(溶)孔、灰岩岩溶缝洞和构造微裂缝,局部发育台缘滩颗粒孔型储层;有效储层发育主要受控于沉积相带、成岩作用、古岩溶风化作用及构造运动,其中潮坪相及台缘滩相为克里摩里组提供了原始储层的物质基础,并在此基础上形成了成岩早期的白云岩晶间(溶)孔和台缘滩颗粒孔型储层;埋藏成岩作用阶段,重结晶作用对原始白云岩储层改造明显,晶体骨架更加稳固,新的晶间(溶)孔形成或经历二次重结晶改造,同时台缘滩颗粒孔的原始结构部分被破坏、充填或改善,形成现今的台缘滩残余颗粒孔;古岩溶风化作用控制克里摩里组中上部岩溶缝洞型储层的发育,高产井主要发育在岩溶斜坡沟槽地带的上槽方向及岩溶高地;多期构造运动不断改造、控制微裂缝系统的发育,形成断裂带周边分布的多孔介质储集体。因此,寻找克里摩里组潮坪相和台缘滩相有利相带、岩溶古地貌上倾部位或断裂带高部位,是下一步勘探的有利方向。In recent years,some progress has been made in the exploration of Ordovician natural gas in the western Ordos Basin,among which,the Ordovician Kelimoli Formation has the highest degree of natural gas accumulation.However,the controlling factors for effective reservoir development are complicated,leading to unsatisfactory explora⁃tion effect.Based on the data of core observation,thin section identification,drilling and logging,the development types and controlling factors of effective reservoir in the Kelimoli Formation were systematically studied,and a deve⁃lopment model of effective reservoir was established.The results show that the effective reservoir types of Kelimoli Formation in the western Ordos Basin mainly include dolomite intercrystal(dissolved)pore,limestone karst fracture and structural micro⁃fracture,and marginal platform granular pore type reservoir is locally developed.The development of effective reservoir was mainly controlled by sedimentary facies,diagenesis,paleokarst weathering and tectonic movement.The tidal flat facies and marginal platform facies provided the material basis for the original reservoir of the Kelimoli Formation,and on this basis,the dolomite intercrystal(dissolved)pore and marginal platform granular pore reservoirs were formed in the early diagenesis.In the stage of burial diagenesis,recrystallization obviously reformed the original dolomite reservoir,and the crystal framework became more stable.New intercrystal(dissolved)pores were formed or underwent secondary recrystallization.At the same time,the original structure of marginal platform granular pores was damaged,filled or improved,and the present marginal platform residual granular pores were formed.Paleo⁃karst weathering controlled the development of fracture-vuggy reservoirs in the middle and upper parts of the Kelimoli Formation,and high⁃yield wells were mainly drilled in the upper groove direction of the karst slope groove zone and karst highlands.The multi⁃stage tectonic movement continuously transformed

关 键 词：有效储层类型 古岩溶 风化作用 成岩作用 克里摩里组 奥陶系 鄂尔多斯盆地西部 

分 类 号：TE122.2[石油与天然气工程—油气勘探]