Analyze and improve the influence of geomagnetic gradient on aeromagnetic compensation in a towed bird

Abstract. Aeromagnetic exploration is an important method of geophysical exploration. We study the compensation method of towed bird system and establish the towed bird interference model. Due to the low altitude of the helicopter, the geomagnetic gradient changes greatly, so the geomagnetic gradient is considered in the towed bird interference model. In this paper, we model the gradient of the geomagnetic field as vertical gradient and horizontal gradient components, analyze the influence of the towed bird system on the compensation results under different motion modes, and apply the ridge estimation method to solve the problem. We verify the feasibility of this compensation method through actual flight tests, and further improve the data quality of the towed bird interference.