川东高陡背斜区水文网控制的地下岩溶空间分异研究

Spatial Differentiation of Underground Karst Controlled by Hydrological Network in High-Steep Anticline in Eastern Sichuan,China

川东隔挡式构造区不同等级的排泄基准面控制了地下水循环,从而影响着岩溶发育,探讨川东地区地下岩溶发育规律,对指导川东高陡背斜区隧道工程选址及建设具有重要的意义。本文基于ArcGIS对岩溶地貌、沟(河)谷水系统计分析,研究了明月峡背斜南段岩溶地貌的空间分布和水文网组合特征,提出水文网控制下的地下水循环模式和地下岩溶发育规律。研究表明:“深、浅切横沟”和“岩溶化山地”组合下的扬起区,其核部地下岩溶弱发育,东、西翼表现为横切沟谷之上岩溶强发育,之下弱发育的二元结构;在“浅切横沟、贯穿型河谷”和“缓丘溶洼”组合下的过渡区,地下岩溶以浅层网状岩溶管道发育;在“贯穿型河谷”和“槽谷洼地”组合下的倾伏区,地下岩溶以阶梯状岩溶管道发育。

Different levels of drainage datum in the parallel barrier structure in Eastern Sichuan control the groundwater circulation,which affects karst development.It is of great significance for exploring the development law of underground karst to guide the site selection of tunnel projects in the karst area of Eastern Sichuan.This paper studied the spatial differentiation and the hydrological network combination characteristics of karst landform in the southern segment of the Mingyuexia anticline based on ArcGIS analysis of karst geomorphology and gully valley water system,and proposed the groundwater circulation model and underground karst development under the control of hydrological network.It illustrated that the uplifting area under the combination of deep and shallow cut transverse ditch and karst mountain was weakly developed in the underground karst,and the east and west wings was characterized by strong karst evolution on the cross-cut valley and weaker,developmental binary structure.The underground karst developed shallow network karst pipeline in the transition zone under the combination of shallow-cut transverse trench,penetrating valley and difficult hill-solvent.The underground karst developed a stepped karst pipeline in the discharge area under the combination of through-flow valley and the slot valley.