Conference Paper

Application of isotope and geochemical techniques to geothermal exploration in southeast of China--A review

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Abstract

Hot springs that are -widely distributed in the SE coastal area of China and there have been a subject of dispute on their genesis and origin. Since mid 80 's, with the support of the IAEA Research Contracts, isotope and geochemical techniques have been systematically applied to the geothermal systems in the region. The techniques have proven to be very useful and effective in geothermal exploration. 2H and 18O have been employed to study the origin and recharge of the systems, -while 3H and 14C have been used to determine the age of the geothermal fluids. Fluid/mineral equilibrium modelling is also useful for the calibration and use of conventional chemical geothermometers and makes reservoir temperature prediction more reliable. Different geothermal systems from Fujian, Guangdong and Hainan Provinces -were selected for the study. Results show that the geothermal systems in the study area all belong to the low-medium temperature geothermal systems ofconvective type, which essentially differs from high temperature geothermal systems with magmatic heat sources underneath.

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... Most successful studies (e.g. Changkuon et al., 1989;Wang and Pang, 1995;Horvatincic et al., 1996) have been conducted using DIC 14 C measurements. Within the time length of the 14 C dating (the production rate of the global 14 C reservoir is more or less constant) the cosmogenic production is balance by radioactive decay. ...
... A simplest approach to carbon-14 dating of groundwater systems assumes that the 14 C ''travel'' with the water molecules along the flow path and the main mechanism that controls carbon-14 dating technique can be routinely performed on DIC by use of accelerator mass spectrometry (AMS) or through a liquid scintillation counter (benzene synthesis). Most successful studies (Changkuon et al., 1989;Wang and Pang, 1995;Horvatincic et al., 1996) have been conducted using DIC 14 C measurements. Within the time length of the 14 C dating method the production rate of the global 14 C reservoir, is more or less constant, the cosmogenic production is balance by radioactive decay. ...
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