Key technology and equipment of ground-airborne wide field electromagnetic method

Ground-airborne electromagnetic method is a key technology for mineral resource exploration. It has high exploration efficiency and strong terrain adaptability. However, traditional technologies have several drawbacks, including low power utilization efficiency of power supply systems, stringent layout requirements of observation systems, significant interference from electromagnetic and motion noise, low signal-to-noise ratio, and shallow exploration depth, which cannot meet the demands of deep, efficient and green exploration. Based on the wide field electromagnetic method, a ground-airborne wide-field electromagnetic exploration system is developed. It adopts wide-azimuth detection technology to realize 360° omnidirectional electromagnetic detection around the source, breaking through the limitation of traditional single-component observation. the a^n+b^n+c^n hybrid-coded pseudo-random signal technology is applied to achieve simultaneous transmission and reception of 39 frequencies in the 8−10 kHz frequency band, which synergistically improves anti-interference ability, exploration efficiency and vertical resolution. Denoising technologies based on transfer functions and deep learning are integrated to accurately suppress ground-airborne electromagnetic noise, efficiently separate signals from noise, improve low-frequency data quality, and increase the maximum exploration depth to 1500 m. The developed ground-airborne wide field electromagnetic exploration system consists of a vehicle-mounted and vehicle-controlled new energy transmitter and a lightweight airborne receiver, which greatly improves energy efficiency and power utilization efficiency. This technology realizes efficient, high-precision and deep green exploration, providing technical support for the new round of strategic breakthrough actions for mineral prospecting in China.