A Study Of Hydrochemistry And Isotopes Of Baimiao Hot Spring, Chicheng Hot Spring And Tangzimiao Hot Spring

Chicheng county of Zhangjiakou lies in the northern mountain area of Hebei province. There are three hot springs naturally emerging from the bedrock mountain in this region: Baimiao hot spring, Chicheng hot spring and Tangzimiao hot spring. The hot springs are characterized by high exposure site, large discharge and high water temperature. Examination of the formation, evolution and development is of great importance.There was a discussion about features of hydrochemistry using AquaChem software, and get a preliminary conclusion of hydrochemical formation and evolution mechanism by comparing their secular variation trend. The utility of isotope method in underground hot water is effective, in this paper, water supply source was confirmed and the temperature, latitude, elevation, residence time of the hot springs was estimated according to the different kinds of effect of the hydrogen, oxygen isotope. Additionally, the deep reservoir temperatures of hot springs was estimated through geochemical thermometers, and there will be a discussion about cold water mixing proportion of Chicheng hot spring. Finally, the paper gives some simple proposals about the hot springs' exploitation and utilization. According to the above work, we get such recognitions: the temperatures of three hot springs are between 41.5℃to 60.8℃, so they all belong to middle-low temperature geothermal resources. The main chemical type of Baimiao hot spring is Na-SO4-HCO3,and that of Chicheng hot spring and Tangzimiao hot spring areNa-SO4.The source of three hot springs are atmospheric precipitation; the calculation of temperature values in recharge areas of Baimiao hot spring, Chicheng hot spring and Tangzimiao hot spring respectively are 6.64℃,5.68℃and 7.02℃;the latitude respectively are 48.08°,50.16°and 47.25°north latitude; the elevations of each recharge areas are 1524 m for hot Chicheng spring and 1181m for Tangzimiao hot spring; the calculation values of the age of hot springs are 67, 12 and 29 a respectively, using radium and radon method. It considered that the source of heat of three hot springs are all from the deep earth thermal source relative to magma, the calculation value of hot springs' circulation depths are respectively 2514, 3729, 3854 m for Baimiao hot spring, Chicheng hot spring and Tangzimiao hot spring. On the other hand, we use methed of geochemical thermometer to predict the deep reservoir temperatures, the temperature ranges are 70-103℃, 112-134℃, 93-121℃,respectively, for three hot springs. According to the feature of ions, Chicheng hot spring has been mixed with cold groundwater, and the proportion of cold water is 70%, and Tangzimiao hot spring has not been mixed with cold groundwater or the proportion is low.There also will be some suggestions suitable for actual conditions in the paper: Baimiao hot spring should be protected first, Chicheng hot spring should keep developing the tourism and consider the heating service for local population in winter; Tangzimiao hot spring can take some agriculture exploitations.