Algorithmic Correction of Magnetometer Device Errors

Abstract

The problems of using gradient measurements in magnetic exploration are considered. In many cases, to solve various geological problems, information on the intensity of the geomagnetic field and its gradients, as measured by special equipment, is important. The results of the development and construction of a three-component fluxgate magnetometer-gradiometer intended for measuring on the earth’s surface the absolute values of the three components of the geomagnetic field strength vector and the corresponding three components of the gradient are presented. Installation in the device of additional measuring sensors – accelerometers, enables one to calculate the orientation of these vectors in space. The device of the magnetometer-gradiometer is described, its functional diagram and the principle of operation are presented. The set of instrumental errors arising in the manufacture of three-axis systems of fluxgates and accelerometers designed for measuring the components of the geomagnetic field strength and determining the orientation of the device is considered. A method of finding instrument errors and algorithmic correction of information signals that come from measuring sensors is presented. It is shown that this method provides a significant increase in measurement accuracy. Examples of field testing of the device are given. The presented magnetometer-gradiometer can be used to accurately localize tectonic disturbances, low-power zones of magnetic mineralization, previously identified ore bodies and determine the details of their structure.