Study on Kunming Low-Temperature Geothermal Field

Abstract

Situated a few hundred kilometers eastwards to the so-called ëHimalayan Geothermal Zoneí in SW-China, Kunming lowtemperature fracture dominated geothermal field has been explored and exploited for spa, feeding fish, growing flowers and drinking as mineral water since 1970s. Nearly one hundred productive wells were drilled one after another during previous years, and a large quantity of hot groundwater was extracted from the reservoir each year. Somehow, a systematic study on the field was lacking. It is essential to establish the conceptual model and furthermore to evaluate geothermal reserve of the reservoir. This study shows that, with a lower conductivity, the unconsolidated overburden in Kunming basin enclose the enormous heat flow that conducts from the deep crust along several huge faults in the base. As a result, the groundwater in the reservoir has been heated up to form a semi-closed and layer-buried low-temperature geothermal field, whose origin comes from rain. Both the area and the stored heat of the field are comparably larger, and the field has been cut into six blocks by the faults. Each block has different characteristics. Further research needs to be conducted to develop a managerial model so as to avoid any potential environmental impacts and utilize the geothermal resource in the best way.