摘要
分析了塔里木盆地塔北隆起西段英买2地区19口井奥陶系地层水矿化度、离子组成、离子比例系数与现今海水的差异,总结了储层发育类型对地层水化学特征的响应特征,结果表明:英买2地区奥陶系地层封闭性较好,水岩相互作用强烈,HCO_3^-、Ca^(2+)随着pH值增大呈现先增大后减小的趋势,钠氯系数随着pH值增大而增大,变质系数呈现相反的趋势。地层水化学特征与储层发育类型有密切关系,在构造翼部的双向断裂控制区,相对孤立的溶蚀洞穴经历了相对较强的溶蚀作用,pH值相对较高,Ca^(2+)因被沉淀而含量相对较低,主要分布洞穴型优质储层。地层水Ca^(2+)高值区主要沿着构造高部位NNE向大型走滑断裂及两侧分布,对应pH值低值区和裂缝-孔洞型储层,活跃的H^+及构造特征使流动的地层水加速了对碳酸盐岩的溶解。英买2地区奥陶系地层水中的Ca^(2+)、HCO_3^-及钠氯系数、变质系数均以pH值为核心具有较好的相互关系,进而能够反映储层类型,这一研究结果对塔北隆起碳酸盐岩岩溶储层的优势发育区预测具有一定的指导作用。
The differences on salinity,ion composition and ion ratio coefficient of formation water from 19 wells in the Ordovician of YM2 area in the western Northern Tarim uplift of Tarim basin and that of the current seawater were analyzed,and the response characteristics of reservoir development types to chemical features of formation water were summarized.The results show that the Ordovician in the YM2 area exhibit good sealing properties and strong water-rock interaction;HCO^3-and Ca^2+present the trends of increasing with pH value firstly and then decreasing;the sodium chloride coefficient increases with increasing of pH value,and the metamorphic coefficient takes an opposite trend.The chemical characteristics of formation water are closely related to the types of reservoir development.For the bi-directional fracture control zone in the tectonic wing,the relatively isolated Karst caves have undergone relatively strong dissolution,the pH value is relatively high,the content of Ca^2+is relatively low due to precipitation,and the cave-type high-quality reservoirs are dominant.The high formation water Ca^2+zones are mainly distributed along the large NNE trend strike-slip fault and its both sides in structural high,corresponding to the low pH value areas and the fracture-cavern type reservoirs;the active H^+and structural features accelerate the flowing of formation water,which facilitates the dissolution of carbonate rock.The Ca^2+,HCO 3^-,sodium chloride coefficient,and the metamorphic coefficient in the formation water of Ordovician in YM2 area have a good correlation with the pH value,which can further reflect the reservoir types.The results of this study can provide guidance for prediction of the dominant developmental zone of the carbonate Karst reservoir in the Northern Tarim uplift.
作者
杨春龙
谢增业
董才源
国建英
张璐
刘知鑫
YANG Chunlong;XIE Zengye;DONG Caiyuan;GUO Jianying;ZHANG Lu;LIU Zhixin(PetroChina Petroleum Exploration&Development Research Institute,Langfang,Hebei 065007,China;CNPC Key Laboratory of Gas Reservoir Formation and Development,Langfang,Hebei 065007,China;CNPC Economics&Technology Research Institute,Beijing 100724,China)
出处
《中国海上油气》
CAS
CSCD
北大核心
2018年第5期55-62,共8页
China Offshore Oil and Gas
基金
"十三五"国家科技重大专项"大型气田形成条件
富集规律及目标评价(编号:2016ZX05007-003)"
中国石油天然气股份有限公司科技项目"天然气成藏动态模拟与保存条件定量动态评价(编号:2016B-0602)"部分研究成果
