Analysis and reduction of the geomagnetic gradient influence on aeromagnetic compensation in a towed bird

Zhijian Zhou,Chao Wang,Yihang Wang,Wenduo Li,Zhilong Liu

doi:10.5194/gi-10-257-2021

Zhijian Zhou, Chao Wang + Show 3 more

Open Access

https://doi.org/10.5194/gi-10-257-2021

Copy DOI

Abstract

Abstract. Aeromagnetic exploration is an important method of geophysical exploration. We study the compensation method of the towed bird system and establish the towed bird interference model. Due to the geomagnetic gradient changing greatly, the geomagnetic gradient is considered in the towed bird interference model. In this paper, we model the geomagnetic field gradient and analyze the influence of the towed bird system on the aeromagnetic compensation results. Finally, we apply the ridge regression 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.

Highlights

Aeromagnetic exploration is generally used in geological research, mineral exploitation, and underground unexploded ordnance detection (Ekinci et al, 2020; Beamish and White, 2011; Doll et al, 2012)
Since the magnetic field generated by the ferromagnetic material and metal-cutting geomagnetic wires on the aircraft platform will interfere with the magnetic detector, it will affect the quality of aeromagnetic survey data
When N = 0, the compensation result is less than the standard deviation improvement rate when N is 1, 2, 3

Summary

Introduction

Aeromagnetic exploration is generally used in geological research, mineral exploitation, and underground unexploded ordnance detection (Ekinci et al, 2020; Beamish and White, 2011; Doll et al, 2012). In 1979, Bickel (1979) analyzed the multicollinearity of the T–L model and proposed a small signal solving method to reduce the linear relationship between features. In 1993, Williams (1993) proposed a neural network nonlinear model to solve aeromagnetic interference, but this neural network model has an overfitting problem. On this basis, Ma et al (2017) proposed a dual estimation compensation method of unscented Kalman filter and suppressed the problem of neural network overfitting by introducing measurement noise. In this paper, based on the towed bird interference model, the geomagnetic gradient component is introduced and solved by the ridge regression method. Through the actual flight data verification, this method can improve the data quality of pod interference

Experiment and data introduction

Error analysis and improvement

Evaluation standard of compensation quality

Results and analysis

Conclusion