Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, 130021, PR China.
Key Laboratory of Groundwater Resources and Environment Ministry of Education, Jilin University, Changchun, 130021, PR China.
Environ Pollut. 2016 Sep;216:340-349. doi: 10.1016/j.envpol.2016.05.076. Epub 2016 Jun 10.
Ordos Basin is located in an arid and semi-arid region of northwestern China, which is the most important energy source bases in China. Salawusu Formation (Q3 s) is one of the most important aquifer systems of Ordos Basin, which is adjacent to Jurassic coalfield areas. A large-scale exploitation of Jurassic coal resources over ten years results in series of influences to the coal minerals, such as exposed to the oxidation process and dissolution into the groundwater due to the precipitation infiltration. Therefore, how these processes impact groundwater quality is of great concerns. In this paper, the descriptive statistical method, Piper trilinear diagram, ratios of major ions and canonical correspondence analysis are employed to investigate the hydrochemical evolution, determine the possible sources of pollution processes, and assess the controls on groundwater compositions using the monitored data in 2004 and 2014 (before and after large-scale coal mining). Results showed that long-term exploration of coal resources do not result in serious groundwater pollution. The hydrochemical types changed from HCO3(-)-CO3(2-) facies to SO4(2-)-Cl facies during 10 years. Groundwater hardness, nitrate and sulfate pollution were identified in 2014, which was most likely caused by agricultural activities.
鄂尔多斯盆地位于中国西北干旱半干旱地区，是中国最重要的能源基地之一。萨拉乌苏组（Q3s）是鄂尔多斯盆地最重要的含水层系统之一，与侏罗纪含煤区相邻。十年来，对侏罗纪煤炭资源的大规模开采对煤矿物质产生了一系列影响，如因降水渗透而暴露于氧化过程和溶解于地下水中。因此，这些过程如何影响地下水质量是人们非常关注的问题。本文采用描述性统计方法、Piper 三线图、主要离子比值和典范对应分析，利用 2004 年和 2014 年（大规模采煤前后）监测数据，研究了地下水的水化学演化，确定了污染过程的可能来源，并评估了地下水成分的控制因素。结果表明，长期的煤炭资源开采并没有导致严重的地下水污染。在 10 年内，水化学类型从 HCO3(-)-CO3(2-)相转变为 SO4(2-)-Cl 相。2014 年发现地下水硬度、硝酸盐和硫酸盐污染，这很可能是农业活动造成的。
