库车坳陷东部阿合组地层水化学特征及其油气响应  

Hydrochemical characteristics and hydrocarbon response of stratum water of Ahe Formation in Eastern Kuqa Depression

作　　者：张海祖 徐同[3,4] 谢亚妮 张慧芳 凡闪[1,2] 陈常超 朱传庆[3,4] ZHANG Haizu;XU Tong;XIE Yani;ZHANG Huifang;FAN Shan;CHEN Changchao;ZHU Chuanqing(R&D Center for Ultra-Deep Complex Reservoir Exploration and Development,CNPC,Korla 841000,Xinjiang,China;Research Institute of Exploration and Development,PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China;State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China;College of Geosciences,China University of Petroleum,Beijing 102249,China)

机构地区：[1]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 [2]中国石油塔里木油田公司勘探开发研究院,新疆库尔勒841000 [3]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [4]中国石油大学(北京)地球科学学院,北京102249

出　　处：《中国地质》2024年第6期2017-2027,共11页Geology in China

基　　金：塔里木油田公司委托科研项目(041020050021);国家科技重大专项(2017ZX05008-004);中国石油天然气集团有限公司攻关性应用性科技专项(2023ZZ14)联合资助。

摘　　要：【研究目的 】地层水作为油气运移的载体,对油气成藏具有重要意义。塔里木盆地库车坳陷东部侏罗系阿合组油气藏的油水分布关系复杂,地层水特征及其与油气藏的关系缺少系统研究。【研究方法 】为了明确地层水化学特征及其与油气藏之间的关系,在对地层水样品筛选的基础上,对库车东部阿合组的地层水测试数据进行分析,研究地层水的水型、矿化度、离子比例系数的分布特征及其油气意义。【研究结果 】阿合组的地层水主要为NaHCO_(3)型,其次为CaCl_(2)型和MgCl_(2)型,矿化度相对较低。地层水的矿化度、离子比例系数具有受构造控制的特点:在构造的开启区、地层的尖灭区,地层水主要为低矿化度的NaHCO_(3)型,钠氯系数、脱硫酸系数较高且变质系数为负值,而封闭性的地层中地层水具有相反的化学特征。【结论 】地层水化学特征与油水层的平面分布特征有较好的耦合关系,以迪北油气藏为例,依奇克里克断裂以北虽经历过油气的充注,但已经生成的油气沿着断裂逸散,低矿化度、高钠氯系数、高脱硫酸系数、低变质系数及高高岭石含量表明地层受到了沿断裂进入大气降水的影响;而断裂以南相反的地层水化学特征及高岭石含量反映地层封闭性较好,受大气降水影响小,对应了气藏的分布。地层水的化学特征与油气藏的分布关系为后续致密油气藏的勘探开发和评价提供一定依据。This paper is the result of oil and gas exploration engineering.Objective As the carrier during the oil and gas migration,stratum water plays an important role in oil and gas accumulation.The oil−water distribution of the Jurassic Ahe Formation(J1a)oil and gas reservoirs in the eastern Kuqa Depression of the Tarim Basin is complicated,and the characteristics of stratum water and its relationship with oil and gas reservoirs are lack of systematic study.Methods In order to clarify the chemical characteristics of stratum water and its relationship with reservoirs,based on the selection among stratum water samples,the test data of Ahe Formation in eastern Kuqa Depression are obtained to study the distribution of water type,TDS and ion−proportionality coefficients of stratum water and its significance to reservoirs.Result The stratum water of J1a is mainly NaHCO_(3) type,followed by CaCl_(2) and MgCl_(2) type,and has relatively low salinity.The TDS and ion−proportionality coefficients of stratum water are controlled by tectonics.In the structure opening area and the pinch−out area of the strata,the stratum water is characterized by NaHCO_(3) type with low TDS,the sodium−chloride coefficient and desulfurization coefficient are high and the metamorphic coefficient is negative.Nevertheless,the stratum water in the closed strata has the opposite hydrochemical feature.Conclusions There is a good coupling relation between the hydrochemical characteristics of stratum water and the plane distribution of oil and water,with Dibei oilfield as an example,although the strata north of the Yiqikelike fault had been charged,the generated oil and gas had escaped along the fault.The low TDS,high sodium−chloride coefficient,high desulfurization coefficient,low metamorphic coefficient,and high kaolinite content indicate that the strata were affected by the meteoric water that entered along the fault.On the contrary,the hydrochemical characteristics and kaolinite content in the strata south of the fault reflect that the format

关 键 词：地层水 离子比例系数 油水分布 油气勘查工程 库车东部 塔里木盆地 新疆 

分 类 号：P618.13[天文地球—矿床学]