Research On Regional Groundwater Circulation Pattern In Caofeidian

The Caofeidian New District is planning to be a populated city area and industrial zone, therefore, to ensure the safety for water supply in caofeidian District, the demand on how to develop and utilize the ground water is put forward. Due to years of groundwater overdraft in part of the district, the fall in water table was sustained, which had already formed the groundwater funnel, and caused some geological environment problems such as seawater intrusion and land subsidence. In the previous research, although the views that the regional groundwater had certain mining potential were presented, there was a lack of study on water circulation in this district, owing to an absence of systematic research on model of groundwater circulation in the Caofeidian District.Aiming to the characteristic that the development and utilization of groundwater were severely affected by human activities, this paper try to bond the groundwater hydrochemistry and isotope technique organically to complement and verify mutually. The isotope D and18O are employed in this paper to determine the recharge source of groundwater and its mutual relationship. For another, the CFCs dating technique is used to determine the groundwater age, thus to set up the groundwater circulation pattern of typical profile that range from the piedmont to Bohai Bay, which, in turn, can improve our knowledge of the characteristics of water circulation in this area based on double action resulted from nature and human beings.A study on dynamics of groundwater is analyzed according to two different orders, namely, the regional and focused area in this paper. This paper also analyzes the spatial distribution law of isotope by regional and typical profile. According to the study, the river water, phreatic water and confined water all originated from the precipitation. The phreatic water regime belongs to precipitation infiltration type, while the confined water regime belongs to runoff type. And further, both the phreatic water and confined water have closely related features with the landscape environment and artificial mining. The north of Zengjiawan is viewed as the main recharge areas, both the hydrochemistry and isotope characteristics consistently showed that the phreactic water is recharged by the river water and the confined water is recharged by the phreatic water. On the other hand, the areas range from the south of Zengjiawan to the coastal area, the groundwater in conditions of supply, runoff and drainage demonstrate that it is stable fundamentally. According to the comprehensive analysis of the water dynamics field, hydrochemistry field coupled with the isotopes, the groundwater systems of Shuanglong River profile are divided into three orders, namely, the shallow circulating system, intermediate circulating system and deep circulating system.This study constructed the regional groundwater circulation patterns in Caofeidian District, it can establish schemes for the water resources utilization of this region, thus provide foundation of guiding rational development and exploitation of groundwater resources in Caofeidian District.