Kamdee Kiattipong, Corcho Alvarado Jose A, Yongprawat Monthon, Occarach Occapasorn, Hunyek Vanachawan, Wongsit Arpakorn, Saengkorakot Chakrit, Chanruang Patchareeya, Polee Chalermpong, Uapoonphol Nichtima, Mabry Jennifer, Romeo Nicolo, Hillegonds Darren, Zappala Jake C, Mueller Peter, Matsumoto Takuya
Thailand Institute of Nuclear Technology (Public Organization), Nakhon Nayok, Thailand.
Nuclear Chemistry Division, Spiez Laboratory, Federal Office for Civil Protection, Spiez, Switzerland.
Isotopes Environ Health Stud. 2023 Oct 9:1-28. doi: 10.1080/10256016.2023.2261613.
Krypton-81 was applied to investigate the age of groundwater in the aquifer system in the Bangkok metropolitan and vicinity areas. Stable (H, O and C) and radioactive (H, Kr and C) isotopes and noble gases were applied in parallel. Low levels of C and significant radiogenic He confirm that groundwater in the deep aquifers is older than 30 ka. Kr analysis identified groundwater with ages ranging from 17 to 300 ka. At some sites, large age discrepancies between Kr and C indicated that inter-aquifer mixing is likely occurring. The interpretation of the noble gases suggests that groundwaters in the deeper aquifers, with apparent ages of 300 to 10 ka, have recharged in slightly colder and wetter climates than those found in the upper aquifers with apparent ages < 10 ka. Degradation of water quality from seawater intrusion was identified in the upper four aquifers. This was also evidenced by higher O and H values, typical of seawater. The four deeper aquifers contain high quality water characterised by less enriched O and H. This work presents new findings of very old groundwater in the Bangkok aquifer system.
氪 - 81被用于研究曼谷大都市区及周边地区含水层系统中地下水的年龄。同时应用了稳定同位素（氢、氧和碳）和放射性同位素（氢、氪和碳）以及稀有气体。低水平的碳和显著的放射成因氦证实深层含水层中的地下水年龄超过30 ka。氪分析确定地下水年龄范围为17至300 ka。在一些地点，氪和碳之间存在较大的年龄差异，表明可能发生了含水层间的混合。稀有气体的分析表明，深层含水层中表观年龄为300至10 ka的地下水，其补给时的气候比表观年龄<10 ka的上部含水层中的地下水补给时的气候略冷且湿润。在上部四个含水层中发现了海水入侵导致的水质恶化。较高的氧和氢值也证明了这一点，这是海水的典型特征。四个较深的含水层含有优质水，其特征是氧和氢的富集程度较低。这项工作展示了曼谷含水层系统中极古老地下水的新发现。
