浅层地下水^3H-^3He法测年技术在石家庄市应用研究

The Application of Shallow Groundwater ^3H-^3He Dating Technique to Shijiazhuang City

^3H-^3He测年法是利用母体^3H衰变成子体^3He这一对核素的衰减和累积原理实现的，它能够很好地取代氚法测年。根据石家庄地区地质和水文地质实际及原有研究基础，选取有代表性的井点取样、测试并计算了各井点浅层水年龄。计算结果与1982年的氚法测年结果对比，具有一致的变化规律，石家庄市浅层地下水年龄从北到南逐渐变大，东南部最大；滹沱河沿岸一带由于近年来黄壁庄水库每年或隔年向滹沱河放水，其浅层地下水年龄较小。总之，^3H-^3He测年法在石家庄市浅层地下水测年应用中取得了比较理想的结果。

The ^3H-^3He dating method is based on the principle that ^3He concentration increases and ^3H concentration decreases with the continual radioactive decay of tritium. This technique can well replace the tritium method in dating. With the financial support by the National NSFC to the project -“The Application of shallow groundwater ^3H-^3He dating technique to hydrogeology”, and based on the actual geological and hydrogeological conditions as well as previous studies in Shijiazhuang area, the authors collected water samples from some representative wells. The ^3H-^3He ages of the shallow groundwater were determined through calculation of the test result. These data show a consistent changing regularity with the tritium ages dated in 1982. From north to south the ages of shallow groundwater gradually increase, with the oldest sample being in the southeast. Along the Hutuo River the ages are rather young, and this is attributed to the recharge by the rivers in recent years. The application of the ^3H-^3He dating method to Shijiazhuang shallow groundwater proves to be very satisfactory.