The Ordos Cretaceous Groundwater Basin,located in an arid-semiarid area in northwestern China,is a large-style groundwater basin.SO_4^(2-) is one of the major harmful components in groundwater.Dissolved SO_4^(2-) conc...The Ordos Cretaceous Groundwater Basin,located in an arid-semiarid area in northwestern China,is a large-style groundwater basin.SO_4^(2-) is one of the major harmful components in groundwater.Dissolved SO_4^(2-) concentrations,andδ^(34)S-SO_4^(2-) andδ^(18)O-SO_4^(2-) in groundwater from 14 boreholes and in gypsum from aquifer were analyzed.Results show that SO_4^(2-) in shallow groundwaters originates from precipitation,sulfide oxidation,and dissolution of stratum sulphate,with a big range ofδ^(34)S values,from-10.7‰to 9.2‰,and addition of SO_4^(2-) in deep groundwater results from dissolution of stratum sulphate,with biggerδ^(34)S values,from 7.8‰to 18.5‰,compared with those in shallow groundwater.This research also indicates that three types of sulphate are present in the strata,and characterized by highδ^(34)S values and highδ^(18)O values-style,highδ^(34)S values and middleδ^(18)O valuesstyle, middleδ^(34)S values and lowδ^(18)O values-style,respectively.Theδ^(34)S-SO_4^(2-) andδ^(18)O-SO_4^(2-) in groundwater have a good perspective for application in distinguishing different groundwater systems and determining groundwater circulation and evolution in this area.展开更多
The WATEQ4F-based 'multiple step method', or the method of running WATEQ4F repeatedly, was used to evaluate the error propagation in computations of water-mineral interactions under the circumstances of consta...The WATEQ4F-based 'multiple step method', or the method of running WATEQ4F repeatedly, was used to evaluate the error propagation in computations of water-mineral interactions under the circumstances of constant and varied temperatures due to the uncertainties of input variables. The results show the following: the errors of water chemistry analysis can strongly affect the modelling results of water-mineral reactions; different input variables (errors) have different effects on the saturation indices (S.I.) of different minerals; in many cases, the S.I. errors of minerals change with temperatures.展开更多
基金supported by the China Geological Survey(grant No.1212010331302)National Science and Technology Project(grant No. 2006BAB01A10)International Atomic Energy Agency(grant No.CPR8012,CPR8017)
文摘The Ordos Cretaceous Groundwater Basin,located in an arid-semiarid area in northwestern China,is a large-style groundwater basin.SO_4^(2-) is one of the major harmful components in groundwater.Dissolved SO_4^(2-) concentrations,andδ^(34)S-SO_4^(2-) andδ^(18)O-SO_4^(2-) in groundwater from 14 boreholes and in gypsum from aquifer were analyzed.Results show that SO_4^(2-) in shallow groundwaters originates from precipitation,sulfide oxidation,and dissolution of stratum sulphate,with a big range ofδ^(34)S values,from-10.7‰to 9.2‰,and addition of SO_4^(2-) in deep groundwater results from dissolution of stratum sulphate,with biggerδ^(34)S values,from 7.8‰to 18.5‰,compared with those in shallow groundwater.This research also indicates that three types of sulphate are present in the strata,and characterized by highδ^(34)S values and highδ^(18)O values-style,highδ^(34)S values and middleδ^(18)O valuesstyle, middleδ^(34)S values and lowδ^(18)O values-style,respectively.Theδ^(34)S-SO_4^(2-) andδ^(18)O-SO_4^(2-) in groundwater have a good perspective for application in distinguishing different groundwater systems and determining groundwater circulation and evolution in this area.
基金This research was partially supported by the Postdoc-toral Science Foundation of China.
文摘The WATEQ4F-based 'multiple step method', or the method of running WATEQ4F repeatedly, was used to evaluate the error propagation in computations of water-mineral interactions under the circumstances of constant and varied temperatures due to the uncertainties of input variables. The results show the following: the errors of water chemistry analysis can strongly affect the modelling results of water-mineral reactions; different input variables (errors) have different effects on the saturation indices (S.I.) of different minerals; in many cases, the S.I. errors of minerals change with temperatures.
