1. Hydrogeology and Environmental Geology Survey Center of China Geological Survey, Baoding 071051,China 2. No.2 Institute of Geology and Mineral exploration of Gansu Bureau of Geology and Mineral exploration and Development, Lanzhou 730020,China
Wudalianchi consists of volcanoes formed in late Quaternary multiple eruption. For the purpose of selecting site for hot dry rock exploration and development, a new round of geophysical exploration was launched. Based on complete magnetic survey data obtained in Wudalianchi in recent years, in combination of magnetotelluric surveying and seismic tomography results, the authors re-understood and explained the existing magnetic exploration data. By a comparison with gravity and magnetic field, the authors emphatically investigated Weishan central type eruption formation volcanic dome structure, magmatic sac dynamic mechanism and geological background reflected by gravity and magnetic field, whose characteristics are different from features of Bijiashan-Laoheishan fissure eruptions. Therefore, the results obtained by the authors can provide geophysical information and evidence for studying and discussing the existence of hot dry rock in the deep part of Wudalianchi volcanic edifice.