环境同位素硫在大同南寒武-奥陶系地下水资源研究中的应用

对山西大同口泉沟南寒武-奥陶系碳酸盐岩地下水(岩溶水)资源的开发研究中,利用不同价态硫富集34S的不同以及硫同位素分馏,主要是硫酸盐和硫化物中δ34S(SO₄2-)、δ34S(HS-)的变化,分析了岩溶水的来源,区分出表征循环交替和补给条件的三种地下水类型和环境,识别出口泉南水文地质区内各个地下水子系统及其相互关系。对岩溶水开发中泉域划分问题,使用硫同位素之间的关系,并结合硫酸盐中氧同位素δ18O(SO₄2-)以及14C关系,表明本区与相邻的两泉域相互独立。岩溶水中δ34S(SO₄2-)、δ34S(HS-)和δ18O(SO₄2-)有很大变幅,神头泉Z1岩溶水有罕见的异常值。

The Use of Environmental Sulphur Isotopes in the Study of the Cambrian-Ordovician Aquifer System in the South of Datong

In the karst groundwater exploration study of the Mouthspring Cambrian-Ordovician (∈-O) carbonate aquifer system which is situated on the southwest of Datong of Shanxi Province, environmental sulphur isotopes were used for identifying the origin of karst groundwater, recognizing the environment of karst groundwater with three kinds characterized by its circulation, discharge and recharge, distinguishing the sub-systems of karst groundwater with its mutual relationships. The difference of enrichment of 34 S in species with different valences, the fractionation of sulphur isotopes mainly the isotopic variations of sulphur compounds including δ³⁴S(SO₄^2-) and δ³⁴S(HS^-) were used for this purpose. The Mouthspring ∈-O aquifer system is different from two neighbouring ∈-O aquifer systems, the Deityhead and the Threefloor, using the relationships of their sulphur isotopes, δ¹⁸O(SO₄^2-) and ¹⁴C. Large variations of δ³⁴S(SO₄^2-), δ³⁴S(SO₄^2-) and δ¹⁸O(SO₄^2-) were found in karst groundwater, however, the anomalous values were occurred in the Z1 spring of Deithead ∈-O aquifer system.