赣江河水主成分及锶同位素地球化学研究

Geochemical Studies on the Main Ions and Strontium Isotopes in the Ganjiang River Water

于2007年11月,系统采集赣江流域枯水期河水样品22个,对其主要离子成份组成和锶同位素比值进行了分析测定,以期获得赣江流域化学风化过程及物质来源信息。研究结果显示,赣江流域河水的离子成分主要来源于硅酸岩和碳酸盐岩两端元混合组成的岩石和土壤的化学风化或溶解,且风化作用在近地表环境中进行。流域水体的化学组成基本代表了典型的硅酸岩地区河流的相应化学组成,显示出与碳酸盐岩地区河流及世界主要河流河水化学组成的差异性,如Si、Na、K等含量较高。其次,赣江河水还显示了受人类活动对水体化学组成的影响较大、以及大气CO2消耗率较高等特点。

Twenty-two water samples were collected from the Ganjiang River during the dry season in November 2007,and major ions and Sr isotope ratios were measured to investigate the potential sources and chemical weathering information of the Ganjiang River Basin.The results showed that major ions in the Ganjiang River water were mainly derived form both end-member mixed composition of the weathering of silicate rocks and carbonate rocks,and also showed that the weathering process mainly occurred in the near-surface environment.The main composition of the Ganjiang River water was representative of the typical chemical composition of the silicate rock area,showing significant differences between the rivers that drainage from carbonate rock areas and those from global major rivers,for example.the high concentrations of dissolved Si,Na,K.Secondly,the main composition of the Ganjiang River water also demonstrated the influence by human activities,as well as a higher consumption rate of atmospheric CO2.