Hot dry rock geothermal resource potential in the Wudalianchi volcanic field, NE CHINA: Implications from geophysical exploration

摘要

Hot dry rock is regarded as the clean energy of the future and is an important part of geothermal resources, with great research value and development prospects. The Weishan volcano, located in the northern part of the Wudalianchi volcanic group, was formed in the Pleistocene, and its age is only (0.57-0.31) +/- 0.05 Ma. This area has a geothermal setting similar to but a younger age than that of the Fenton Hill volcano (formed 1.40-1.10 Ma) where a hot dry rock power project has operated since 1973. In this study, we used ambient noise tomography and magnetotelluric sounding methods to investigate deep heat sources beneath the Weishan volcano. The results show good geothermal conditions for hot dry rock formation in this region. A cooling magma chamber that might be the hot dry rock heat source is indicated in the upper crust at 6.5-13 km depth, with a volume of similar to 200 km(3). Our study suggests that the monzonitic granites of the Indosinian Xiaohongshan unit, which lies beneath the Late Cretaceous Nenjiang Formation and the Neoproterozoic-Early Cambrian Beikuanhe Formation, should be the main target for further hot dry rock geothermal energy exploration and development.