新疆南天山岩溶系统介质结构特征及其水文地质效应

Characteristics of Karst Medium System and Its Hydrogeologic Effect in the South Tianshan, Xinjiang

南天山广泛出露碳酸盐岩地层,其岩溶系统功能取决于岩溶介质结构.通过岩溶调查、分析,揭示该区碳酸盐岩地层中普遍分布溶蚀构造裂缝、层间溶蚀裂缝和溶蚀节理缝,其中溶蚀构造缝密度达1～4条/10 m、面隙率达1.15%～5.71%、缝宽10～500mm,在岩层中呈网脉状,穿层发育,各种岩溶缝隙组合构成了以岩溶裂隙-溶缝为介质特征的岩溶系统.据此分析溶蚀缝隙体系对降水入渗、水流运移储存的意义,阐明该体系在水循环过程中的导储功能及其利用条件.提出采取工程措施,将岩溶山区的地表径流转化为地下渗流,增加降水入渗补给入渗量;同时减少水资源的蒸发损失,加大山区侧渗径流量,增加盆地边缘区的地下水资源,探索缓解山前塔里木盆地边缘地区水资源紧缺、改善盆缘地区生态环境的新途径.

Carbonate rocks are widespread along the south Tianshan, where the function of karst system depends on the texture of karst medium It＇s found that there are a lot of solution tectonic fissures, interlayer solution fissures, and solution joints in the carbonate rock strata through the karst investigation and analysis. According to the statistics, the density of solution tectonic fissures is to 1-4 per 10 m width, the fissure ratio on plane to 1. 15%-5.71%, and the width of fissures to 10-500 mm, which are netted distribution and developed cross beds. The combination of all kinds of fissures compose a complicated karst system with the medium of fissure-solution fracture. The significance of the solution fissures system for the precipitation infiltration and water storage is analysed, and its function of transmission and storage in the process of hydrological circle is clarified as well. At last, a new method of relieving the lack of water resources and renovating the karst environment at the edge of Tarim basin is put forward, namely translating the surface runoff into underground seepage and reducing the evaporation in order to increase the recharge of precipitation in karst mountain areas through engineering measures.