SMethodology and Application of Deep Geothermal Sounding in Low-Resistance Cover Areas
Qiao Yong, and Zhang Hui*
1. College of Geosciences, Yangtze University, Wuhan, 430100, China
2. College of Geosciences and Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450000, China
3. China Renewable Energy Engineering Institute, Beijing,100120, China
Abstract:
Taking the Qihe area as an example, this paper compared various geophysical exploration methods in view of the problems of urban construction, deep thermal reservoir burial, and vast overlying low-resistance shield layer in deep karst geothermal exploration. A Controlled-source audio magnetotelluric (CSAMT) method was taken to overcome the problems and detect deep stratigraphic structures in the study area. The acquisition parameters of CSAMT were optimized to take into account the exploration depth and signal-to-noise ratio. The distortion of data in the near and transition zone was eliminated by the inversion of equivalent whole-region apparent resistivity, so as to achieve the purpose of deep sounding. Based on the resistivity profile resulting from the proposed CSAMT method, three faults were inferred and one low-resistance anomaly zone in the area was traced. The results of the profile interpretation were verified by drilling. The inferred stratigraphic boundaries and low-resistance anomaly zone were basically in agreement with the drilling results, thereby proving the effectiveness of the CSAMT method for deep geothermal exploration in low-resistance coverage areas. This method could provide technical support for deep geothermal exploration in similar areas.
作者简介: Qiao Yong (1986 -), since 2019 he has been studying for his Ph.D. at College of Geosciences, Yangtze University, Wuhan. His main research direction is geothermal exploration and development, geothermal policy research.
E-mail: 89561564@qq.com.