Formation of the shallow groundwater in the Northern Henan Plain based on isotope ananlyses

Precision of assessment of groundwater resources is greatly affected by many indeterminacy factors in items of charge and discharge of a groundwater system.Increase of the precision of assessment of groundwater resources is of important significance to hydrogeologists.This paper introduced three means to enhance the precision of assessment of groundwater resources examining the replenishment of the shallow groundwater.(1) Combination of elements and change in isotope contents in groundwater can reflect the change in quantity of groundwater resources.Recharge items of groundwater resources are determined and portioned in this paper with isotope techniques.(2) The recharge quantity of the local river with 131I element flowing velocity is calculated.(3) The proportion recharged by the Yellow River the in groundwater resources is calculated with contents of 18O.As a result,precision of assessment of groundwater resources is indirectly enhanced.In addition,estimation of the renew velocity of the shallow groundwater is also helpful in the assessment of groundwater resources,and is importance in sustainable use of groundwater resources.Attempt is also made to estimate the renewable velocity of the shallow groundwater with contents of T(3H) element in groundwater.