Magnetic gradiometry with a low-cost magneto-inductive sensor: A case study on Baba-Ali iron ore deposit (Western Iran)

Abstract

Recently, the magneto-inductive (MI) magnetometers are commercially available off-the-shelf (COTS). Thanks to their low price, size, weight, power consumption, and fairly good resolution, these low-cost magnetometers are of interest to scientists in various fields of study. Inspired by a magnetic gradiometry magnetometer, we set up two MI sensors with a spacing of around 70 cm and performed a magnetic survey along 8 profiles on Baba-Ali iron ore deposit in western Iran with a proton magnetometer as a standard magnetometry survey instrument. These measurements are performed simultaneously with the set-up magnetometer. The comparison of proton magnetometer and MI sensors measurements shows that even the slight changes in the Earth’s magnetic field appeared on the proton magnetometer measurements also are displayed in the set-up MI magnetometer. Also, we showed that in high gradients which the proton magnetometer has a problem to measure a magnetic field the MI sensors can measure the Earth’s magnetic field.