滦河口河岸砂质潜水含水层渗透系数尺度效应分析研究  

Study on the scale effect of hydraulic conductivity in the sandy shallow groundwater aquifer at Luanhe River Estuary

作　　者：杨轶群 李燊琰 戴君一 高迪[1] 周诗雨 王礼春 YANG Yiqun;LI Shenyan;DAI Junyi;GAO Di;ZHOU Shiyu;WANG Lichun(School of Earth System Science,Tianjin University,Tianjin 300072,China;Tianjin Bohai Rim Coastal Earth Critical Zone National Observation and Research Station,Tianjin 300072,China;Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim,Tianjin 300072,China)

机构地区：[1]天津大学地球系统科学学院,天津300072 [2]天津环渤海滨海地球关键带国家野外科学观测研究站,天津300072 [3]天津市环渤海地球关键带科学与可持续发展重点实验室,天津300072

出　　处：《地学前缘》2025年第3期425-435,共11页Earth Science Frontiers

基　　金：国家重点研发计划项目(2021FY101001);国家自然科学基金重大项目(42293262)。

摘　　要：渗透系数(K)是表征地下水流动和含水层特征的关键水文地质参数,但在不同尺度上河岸带潜水含水层渗透系数的差异性分析尚缺乏系统性研究。本研究以滦河口河岸带松散砂质潜水含水层为研究对象,结合变水头室内渗流实验、野外微水试验以及解析解反演三种方法,从室内土柱尺度(小尺度)、野外钻孔尺度(中尺度)和场地尺度(大尺度)系统分析了含水层的渗透系数特征。研究结果表明,随着研究尺度的增大,渗透系数逐渐升高,三种尺度下的渗透系数的中值分别为0.71 m/d、12.31 m/d和191 m/d。在小尺度下,渗透系数反映了含水层局部异质性特征;随着尺度的增大,形成了更多的优先流路径,渗透系数显著增大;而在场地尺度上,渗透系数表现为含水层整体等效后的结果。由于不同尺度下渗透系数存在显著差异,在研究河岸带地表水-地下水交换通量、海水入侵等潜水含水层中地下水运动过程时,需要谨慎选择与研究目标和工程需求相匹配尺度的渗透系数。本研究为滦河口地区潜水含水层的开发利用提供基础数据支持,同时可为其他区域含水层渗透系数的尺度转换提供借鉴。Hydraulic conductivity(K)is a fundamental hydraulic property for characterizing groundwater flow.However,studies on the variation of K in riparian shallow aquifers at different scales are rare.This study focuses on the loose sandy unconfined aquifer of the Luanhe River Estuary.We used three methodologies,including laboratory permeability test,slug test,and analytical inversion,to calculate effective K at the core,well-bore,and field scales.The findings reveal a clear trend of increasing K with scales,with the median K values of 0.71 m/d,12.31 m/d,and 191 m/d at the corresponding scales,respectively.At smaller scales,the measured K captures the local heterogeneity of the aquifer.As the scale increases,more preferential flow paths are included,leading to a remarkable increase in K.At the large scale,the parameter reflects the homogenized characteristics of the aquifer system as a whole.The significant differences in K across scales highlight the importance of selecting scale-appropriate values tailored to specific engineering requirements and research objectives when studying groundwater-related processes,such as groundwater movement in unconfined aquifers affected by seawater intrusion and surface water-groundwater exchange.Moreover,this study provides essential data for the development and utilization of the aquifer in the Luanhe River Estuary,offering valuable methodological references for understanding water movement within aquifers in other regions.

关 键 词：渗透系数 尺度效应 砂质潜水含水层 

分 类 号：P641[天文地球—地质矿产勘探]