浅析河南省中深层地热流体同位素特征

Analysis on isotopic characteristics of the middle and deep geothermal fluid in Henan

河南省平原地区蕴藏着丰富的地热资源,不同构造单元,不同时代的天然地热流体,其水化学特征及成生环境有较大差异。研究地热流体同位素特征可以了解地热流体来源、年龄、热储温度,同时推断补给、径流和排泄更新周期,对保持地热清洁能源可持续开发利用具有指导意义。通过采用稳定同位素(D、^(18)O)的组成变化判别地热流体的来源或补给源,采用放射性同位素(^(13)C-^(14)C)的衰变规律判断地热流体年龄及补给更新速率,进而得出:地热流体主要来源于大气降水,主要补给区为西部低山丘陵区,平原区地热水年龄在1265 a~39443 a之间,运移速率为2.5 m/a~8 m/a。为河南省地热资源评价提供了数据参考。

There are abundant geothermal resources in the plain area of Henan Province.Natural geothermal fluids of different tectonic units and ages have different hydrochemical characteristics and growth environments.The study of isotopic characteristics of geothermal fluid can understand the source,age and thermal storage temperature of geothermal fluid,and it can also infer the renewal cycle of recharge,runoff and discharge,which has a guiding significance to maintain the sustainable development and utilization of geothermal clean energy.In this paper,the composition variation of stable isotopes(D,^(18)O)is used to judge the source or recharge source of geothermal fluid,and the decay regularity of radioisotopes(^(13)C-^(14)C)is used to judge the age and recharge update rate of geothermal fluid.It is shown that the geothermal fluid mainly comes from atmospheric precipitation,the main recharge area is the western low mountain and hilly area.The geothermal water age in plain area is between 1265 a and 39443 a,and the migration rate is about 2.5 m/a-8 m/a.It provides the data reference for the evaluation of geothermal resources in Henan Province.