| The thesis relys on the sub-topics Lingwu Daquan groundwater circulationmechanism research of the implementation project named “groundwater explorationin Ningdong energy base†by the Geological Survey of China Geological SurveyBureau （water [2010] mineral assessment01-04-20）.This study is mainly on the basisof analysing of the hydrogeological conditions and dynamic characteristics ofgroundwater, using the marks of water chemical and isotope and the timingcharacteristics of the radioactive isotopes to create groundwater circulation patternand estimate the groundwater circulation age.LingWu Daquan has been planed as a important backup water source ofNingdong energy base.Although Yellow River water resource is important in thisstudy area, with the construction of Ningdong energy and chemical base, the demandfor water will continue to increase. LingWu Daquan surface water and groundwaterresources are abundant, but compared to the water of the Yellow River, groundwater ismore convenient touse in the energy base. Mainly due to:（1） Yellow River water ismore turbid,easy to plug the pipelines during the transport, and Yellow River water iseasy to contaminated;（2） LingWu Daquan regional has more groundwaterresources, water quality is well, and less susceptible to contamination. So it isnecessary to set up Groundwater circulation patterns of the study area and to estimatethe groundwater circulation age.First, groundwater circulation patterns in LingWu DaquanGroundwater circulation patterns reflect the general characteristics ofgroundwater recharge, runoff, discharge in the study area, using the followingmethods and means to study the groundwater circulation patterns:（1） characteristicsof groundwater dynamic, the distribution of flow field is basically same in thephreatic aquifer and confined aquifer, the trend is consitent with the terrain. General,the groundwater flow direction is from east to west, from southeast to northwest, fromsouth to north, groundwater pools to plain finally, points to Yellow River. General,phreatic cross-flow supplys confined aquifer.（2） hydrochemistry, The law of thedistribution of Cl-concentration of groundwater is high in the south and north, lowin the middle of the area. The Cl-concentration is relatively low from Qingtongxia to Daquan, and from Changliushui to Daquan, we conclude that Daquan town acceptsthe groundwater recharge from Changliushui.（3） environmental isotope methods, TheδD andδ18O are close in the phreatic water and confined water, combined with thehydrodynamic in the study area, we concluded that phreatic water and confined waterhave close hydraulic connection. The values ofδD andδ18O of groundwater in thelow platform close to atmospheric precipitation, we concluded that the rechargesources of groundwater in the low platform are precipitation. The values ofδD andδ18O of groundwater are gradually reduced from east to west, because of irrigation.The values ofδD andδ18O of groundwater are less than the Yellow River water inWuzhong and Jinji, suggesting that the groundwater accepts recharge of groundwaterwith lowerδD andδ18O values.3H can be used to study the aquifer is or notaccepting the modern water supply.14C can be used to calculate the ancientgroundwater age, and play the role of tracer. Combined with the above technicalmeans to establish the groundwater circulation patterns in the study area.The recharge source of groundwater in low platform is meteoric water, rechargethe low platform through the rock fissures, fault fracrure zone. Phreatic water inalluvial, lacustrine plain area accepts the recharge of fissure water and Yellow Riverwater. The hydraulic connection of phreatic aquifer is closed with the confined aquifer,phreatic aquifer recharges the confined aquifer in the most place, confined aquiferrecharges the phreatic aquifer in the Lingwu and east of Daquan township. YellowRiver has received a lateral recharge of groundwater. The distribution of flow field isbasically same in the phreatic aquifer and confined aquifer in alluvial, lacustrine plainarea, from low platform point to the plain area, excrtion path of groundwater cocluesartisanal mining,evaporation,groundwater lateral flow. The recharge of groundwaterin Daquan township is not only Yellow River water, but also the lateral recharge ofgroundwater in Changliushui.Second, groundwater Renewablity Evaluation in LingWu DaquanThe main recharge source of low mesa groundwater is precipitation, and then thelow mesa groundwater through the rock fissures, fault fracture zone supply to the lowplatform margin. The phreatic water in alluvial and lacustrine plain area is rechargedby Yellow River water and mesa fissure water infiltration, the phreatic water contactclosely with confined water, and it recharge the confined water in most locations. The groundwater in Daquan town is recharged no mater from Yellow River, but fromChangliushui and Qintongxia groundwater.Apply different correction model to calculate the14C age of groundwater, theages of most groundwater samples are older than2000years, and calculate thegroundwater circulation rate is0.9m/year. The renewablity of confined water is weakthan phreatic water. |
