Abstract:The only natural hydrogen sulfide-containing spring that has been discovered in Shandong province is located at the northeastern part of Dawenkou basin which is 25km southwest of Tai'an city. The spring water is light green and green. Because it has a strong smell of rotten eggs, it is called Chouquan spring. The boundary of Chouquan spring is controlled by stratum lithology, fault structure and burial conditions. The aquifer is gypsum mudstone limestone in the third section of Dawenkou formation of Paleogene Guzheng group. Rock is densely honeycomb-like dissolution. Groundwater receives the infiltration and recharge of Quaternary pore water from aquifer outcrop. It gradually becomes confined and dissolves a large number of gypsum components in the rock during runoff movement to the discharge area, thus SO4 Ca type water was formed. Under the action of organic matter, sulfate ions in water under the closed reduction environment will occur esulphurization, and hydrogen sulfide is reduced and dissolved in water. Backwater phenomenon occurs when groundwater meets water-blocking fracture at the spring point, which causes water level to rise and spill over to the surface to form springs. Sulfate ion is the donor of hydrogen sulfide. Based on the results of hydrogen and oxygen isotope analysis, the age of hydrogen sulfide-containing water and the condition of recharge and drainage have been analyzed. At the same time, the groundwater dynamics and geochemical characteristics of water and soil are revealed.
