明月峡背斜南部张关—排花洞岩溶水系统地下水径流模式解析  

Analysis of groundwater runoff patterns in Zhangguan-Paihuadong karst water system in the south of the Mingyue gorge anticline

作　　者：于斯遥 秦梓萱 杨艳娜[1] 毛唯娜 郝朝 许模[1] 刘洋[3] YU Siyao;QIN Zixuan;YANG Yanna;MAO Weina;HAO Chao;XU Mo;LIU Yang(State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection,Chengdu University of Technology,Chengdu,Sichuan 610059,China;Chongqing City Construction Investment(group)Co.Ltd.,Chongqing 400020,China;Chongqing Survey Institute,Chongqing 400020,China)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]重庆城投基础设施建设有限公司,重庆400020 [3]重庆市勘测院,重庆400020

出　　处：《中国岩溶》2022年第4期599-609,共11页Carsologica Sinica

基　　金：国家自然科学基金项目“隔档式构造区岩溶地下水流系统模式及演化规律研究”(42072283)。

摘　　要：川东明月峡背斜地下岩溶发育的强烈非均质性造就了独特的地下水径流模式,孕育出区域复杂的岩溶工程水文地质问题,查明明月峡背斜南段地下水径流模式对指导区内隧道工程选址及建设具有重要意义。文章在已有研究基础上,以“张关—排花洞”岩溶水系统为研究区,通过系统厘清区内水文地质条件,深入剖析区内地下水水文地球化学特征及水动力条件,明确区内岩溶含水介质不均一性控制下的地下水小尺度径流规律。结果显示:研究区地下水在平面上表现为形似“扫帚状”的径流模式:在补给、径流区,三叠系下统嘉陵江组一段(T_(1)j^(1))、嘉陵江组三段(T_(1)j^(3))地层(强岩溶化)与嘉陵江组二段(T_(1)j^(2))、嘉陵江组四段(T_(1)j^(4))地层(弱岩溶化)呈间互状分布的特点导致相邻地层之间水力联系较弱,以地层为单位形成多个相对独立的岩溶水子系统;在研究区排泄区,受控于势汇最强的T_(1)j^(3)内部管道流对其他地层地下水持续的袭夺效应,地下水统一汇聚至排花洞暗河出口向御临河排泄,各岩溶水子系统最终整合为一个岩溶水系统。The long-term interaction between groundwater and karst development in eastern Sichuan has created a unique groundwater runoff pattern and caused a complex hydrogeological problem of karst engineering.Hence,finding out the groundwater runoff pattern in the southern section of Mingyue gorge anticline is of great significance for guiding the site selection and construction of tunnel engineering in this area.Based on previous studies,hydrogeological conditions of the study area are systematically sorted out.Mingyue gorge anticline is a typical closed one in eastern Sichuan,and there is no fault in the area.Atmospheric rainfall is the main recharge source in the water system.Controlled by the boundary of the non-soluble rock formation on the two sides of anticline and topographic relief,groundwater converges and is recharged through the karst structures such as depressions and sinkholes,flowing toward the river runoff at the lowest discharge datum along the tectonic line within the region.The outlet of S05(Paihuadong),exposed on the bank slope of Yulin river,is a main discharge point of groundwater in the system.The discharge is about 365 L·s-1 in the dry season,accounting for 95.94%of the total discharge of all natural groundwater outcrops in the study area.Main aquifers in the area are composed of carbonate rocks of Jialingjiang formation and Leikoupo formation.The lithology of T_(1)j^(1) and T_(1)j^(3) is mainly limestone,while the lithology of T_(1)j^(2),T_(1)j^(4) and T_(2)l is mainly dolomite.The difference of rock solubility results in different karst development in each aquifer.From the perspective of surface karst phenomenon,the area of depression and the number of falling holes developed in T_(1)j^(1) and T_(1)j^(3) strata respectively account for 67.38% and 69.84%of the total amount of the system.From the perspective of underground karst phenomenon,121 karst caves have been revealed by 22 boreholes in the study area.The number of karst caves distributed in T_(1)j^(1) and T_(1)j^(3) strata accounts for 75.

关 键 词：川东褶皱带 明月峡背斜 张关—排花洞岩溶水系统 地下水径流模式 小尺度 

分 类 号：P641.13[天文地球—地质矿产勘探]