Abstract:

The research on the geothermal resources in Jingbo Lake graben of the Dun-Mi fault zone in Heilongjiang Province provides an example to acquire the formation rule of geothermal resources in the sag part of the large fracture zone.Jingbo Lake graben, the regional geological structure of which belongs to the northeast part of the Tan-Lu fault zone, expands in the form of the long strip.The graben has quite deep sedimentary rock layer which contains Neogene system and Paleogene system,the very high geothermal gradient that is 3.2-4.0℃/ hm.The temperature is 90.8 ℃ at 2,500 m deep underground and the geothermal fluid output per unit is 54 m3/(d·m).The results show that geological conditions of geotherm is very favourable.The integrated and calculated data show that the Jingbo Lake graben can be a large-scale geothermal field. By the geothermal fluid output per unit of geothermal well and the evaluation indicators of the suitable classification of the geothermal water exploitation，this geothermal field belongs to the most suitablely exploited geothermal field that has the rich geothermal output. The discovery of geothermal field of Jingbo Lake graben has the positive guidance for seeking out the geothermal resource in the Dun-Mi fault zone, Yi-Shu fault zone and the Tan-Lu fault zone.

Key words: Dun-Mi fault；Jingbo Lake graben；geothermal resources；geothermal water； , Tan-Lu fault zone, Heilongjiang Province