地层水化学特征及水体产能解释——以库车坳陷克深地区巴什基奇克组为例  

Chemical characteristics of formation water and interpretation of water body productivity:a Case study of the Bashijiqike Formation in Keshen Area

作　　者：谷晓强 GU Xiaoqiang(School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an 710065,Shaanxi,China;Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi′an Shiyou University,Xi’an 710065,Shaanxi,China)

机构地区：[1]西安石油大学地球科学与工程学院,陕西西安710065 [2]西安石油大学陕西省油气成藏地质学重点实验室,陕西西安710065

出　　处：《石油地质与工程》2025年第2期95-100,共6页Petroleum Geology and Engineering

摘　　要：地下水是油气流转的动力和载体,其地球化学特性和流动模式与油气的产生、迁移、聚集、保存紧密相关。库车坳陷克深地区以CaCl_(2)水型为主,表现为高矿化度;总矿化度与Cl^(-)和Na^(+)+K^(+)离子浓度呈正相关;Mg^(2+)和Ca^(2+)离子浓度随总矿化度升高而增大;SO_(4)^(2-)和HCO_(3)^(-)离子浓度与总矿化度呈散点关系;地层水水型可划分为过渡带水、夹层水、凝析水及水层水四类。克深地区巴什基奇克组地层凝析水对产能的影响相对较小,产水量通常较低,气井往往能够实现高产气流量,且能保持稳定;夹层水体由于规模有限,产能受致密层影响,致使产能差异显著,通常气井初始阶段,水的产出量相对较高,后随开采持续,气体产出量逐步上升,产水量则逐渐减少;水层水几乎没有任何工业性产能;过渡带水体特征通常具较低的油压、少量的产气量和产水量,不具备工业开采的价值。明确地层水的不同类型,可为准确把握气藏规模提供相应的参考依据,对油气勘探开发具有一定的指导意义。Groundwater is the driving force and carrier of oil and gas circulation,and its geochemical characteristics and flow patterns are closely related to the generation,migration,accumulation,and preservation of oil and gas.The study area is mainly characterized by CaCl_(2)water type,exhibiting high salinity.The total salinity in the study area shows a positive correlation with Cl^(-)and Na^(+)+K^(+);the concentrations of Mg^(2+)and Ca^(2+)ions increase with the rise in total salinity,SO 42-and HCO 3-show a scattered relationship with total salinity.The types of formation water are divided into transition zone water,interlayer water,condensate water,and aquifer water.Located in the Cretaceous Bashijiqike Formation of the Kelausu structural belt,the impact of condensate water on productivity is relatively small,with gas wells often achieving high gas flow rates,while the water production is usually low and stable.Interlayer water typically sees a relatively high water output in the initial stage of gas well production,but as the extraction process continues,the gas output gradually increases while the water production gradually decreases.Aquifer water almost has no industrial productivity,while transition zone water is characterized by low oil pressure,minimal gas and water production,and therefore does not have industrial exploitation value.Therefore,identifying the different types of formation water is meaningful for oil and gas exploration and development,providing a good reference for grasping the scale of gas reservoirs in the future.

关 键 词：塔里木盆地 库车坳陷 白垩系巴什基奇克组 地层水 化学特征 

分 类 号：TE122.2[石油与天然气工程—油气勘探]