基于环境同位素分析吐鲁番盆地地下水流系统

An analysis of the groundwater flow system based on environmental isotopes in Turpan basin

吐鲁番盆地是中国重要的煤炭基地之一,研究盆地地下水流系统对于区域水资源评价具有重要意义。通过在野外开展取样工作,首先根据取样点井深的不同,将所有样点分为4组,结合当地水文地质条件、同位素值的高程效应以及取样点位置,将同位素值以及位置相近的点归为同一个水流系统。经分析,在火焰山以北存在一个相同型式的地下水流动系统,而在火焰山以南随着山区坎尔其水库的修建,水利工程设施的不断完善和农业灌溉制度的改革,存在多级地下水流动系统,其形成条件主要受自然和人类活动影响。其中同位素和TDS值都较高的T1点曾是艾丁湖湖面的边缘,当时湖水水位浅,同位素蒸发效应明显。同时,火焰山地下基岩存在缺口,存在北盆地向南盆地的地下水补给。

base in China, and studying the regional groundwater flow system is of greatsignificance for regional water resources research. The well depths of the sampling points are mainly concentrated in more than 100meters and less than 30 meters. All the samples can be divided into four groups based on the well depth,and in combination with theelevation effect of the isotope value and the locations of the sampling points, the nearby points are grouped into the same watersystem. An analysis shows that the north of the volcanic rocks belongs to the same type of groundwater flow system,while the watersystem in the south of the volcanic rock exhibits features of multistage flow system because of the reservoir building, the continuousimprovement of the water conservancy facilities and the reformation of agricultural irrigation system; its forming condition is mainlyinfluenced by natural and human activities. The isotope and TDS values of T1 point are higher, so it might have been the edge of theAydingkol Lake, and the lake water level was shallow and isotope evaporation effect was obvious at that time. At the same time,loopholes were existent in the bedrock, the groundwater could flow from the north to the south of the basin.