Reinjection Test in Fractured Reservoir in Sanlifan Warm Spring Area, Hubei Province, China

Abstract

A reinjection test carried out for 118 days in small fan low temperature geothermal field (China) which covers an area of only about 0.8 A total of 22,690 of local river water was pumped into the fracture zone standing in Archaean gneiss. During the reinjection test the well temperature and artesian flow rate increased. Water chemistry reflected variations coming from both thermal and cold waters. The anisotropic hydraulic behaviour of the fractured reservoir was verified by the test. The reinjected cold water promotes deeper fluid flow in the reservoir, and the mass flow of deeper hot fluids increased. At same time cold water mixed with hot water in the shallow part of the reservoir. The study indicates that reinjection into a fractured reservoir under certain conditions can produce economic and social benefits.