Abstract:

The ³H method and CFCs method were applied to date the Quaternary shallow groundwater in order to study the groundwater cycle and renewability evaluation of shallow groundwater in Henan Plain. It can be concluded that the fitting error was small (2 a) so that the ages calculation by the two methods can represent the shallow groundwater ages in Henan Plain. In general, the shallow groundwater was the modern recharged water which was younger than 50 a. The groundwater age was younger than 30 a in the piedmonts of Taihang Mountain, Funiu Mountain, Dabie Mountain and along two sides of the Yellow River on west of Kaifeng. The age increased along with the groundwater flow path. The exploration potential decreased from the piedmonts and the two sides of the Yellow River to the plain. In general, the groundwater cycle was faster in the northern groundwater system of which age was younger, followed by  that in the southern groundwater system. The groundwater cycle was the slowest in central groundwater system of which age was the oldest.

Key words: tritium, chlorofluorocarbons, shallow groundwater age, Henan Plain, groundwater