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The contents of D, 8O, 3H and 14C, distinctive in shallow and deep Quaternary aquifers beneath northern China, reflect differences in average paleoclimatic conditions between the Holocene and the last glacial period in Pleistocene. Groundwater in deep confined aquifer was recharged during the last glacial period. The depletions of δ(D) and δ(18O) of this water, 4×10-3-16×10-3 and 1×10-3-2×10-3 when compared with the shallow water recharged in Holocene, suggest that the annual mean temperature was lower in the last glacial period than that in the Holocene. The continental gradient of D and 18O found in old groundwater is essentially similar to that in Holocene, suggesting that the atmospheric circulation did not undergo substantial changes over northern China for the past 30 000 years in spite of the changes in the temperature. Groundwater isotopic stratification indicates three different recharge mechanisms and the influence of modern hydrological circulation, which are very important for the understanding of the continental hydrological circulation and the sustainable development of groundwater resources.
The contents of D, 8O, 3H and 14C, distinctive in shallow and deep Quaternary aquifers beneath northern China, reflect differences in average paleoclimatic conditions between the Holocene and the last glacial period in Pleistocene. Groundwater in deep confined aquifer was recharged during the last glacial period. The depletions of δ (D) and δ (18O) of this water, 4 × 10 -3 to 16 × 10 -3 and 1 × 10 -3 to 2 × 10 -3 when compared with the shallow water recharged in Holocene suggest that the annual mean temperature was lower in the last glacial period than that in the Holocene. The continental gradient of D and 18O found in old groundwater is essentially similar to that in Holocene, suggesting that the atmospheric circulation did not undergo substantial changes over northern China for the past 30 000 years in spite of the changes in the temperature. Groundwater isotopic stratification indicates three different recharge mechanisms and the influence of modern hydrological circulation, which are very im portant for the understanding of the continental hydrological circulation and the sustainable development of groundwater resources.