1. Akuisisi dan Komparasi Data Geomagnetik Menggunakan Proton Precession Magnetometer (PPM) dan Smartphone Magnetometer

Abstract

This research aims to explore the utilization of magnetometer sensors in smartphones for geophysical investigations related to geomagnetic fields. Smartphones are equipped with magnetometer sensors that can be employed as alternative instruments in geomagnetic surveys, offering cost-effective and more accessible options compared to industrial-grade instruments. This experiment utilized an Android-based smartphone magnetometer supported by the Phyphox application. The Geometrics PPM G-857 Industrial-scale Geomagnetic Magnetometer was also employed as a benchmark and for data control. Field acquisitions were conducted in an area with an underground gas pipeline network, which was expected to be a source of subsurface anomalies. The research results indicate that the Smartphone Magnetic Anomaly Maps (TMI & RTP) exhibit similar trends to the Geometrics PPM G-857, although there are discrepancies in anomaly values of up to approximately 1000 nT. The smartphone results also demonstrate higher frequency anomalies, possibly attributed to electronic components within the smartphone itself acting as sources of noise. Gaussian filtering was applied to suppress anomalies with wavelength spectra shorter than 3m (higher frequencies). Additionally, a Bandpass filter was utilized to allow regional signals to pass through, and the outcomes showcased consistent anomaly responses between both the smartphone and PPM G-857. The combined use of Gaussian and Bandpass filters enhanced the anomaly response of the gas pipeline, highlighting it as a high magnetic anomaly. While the anomaly response of the smartphone magnetometer is not as accurate as that of the PPM G-857, this experiment effectively establishes the potential of smartphone magnetometers for use in geomagnetic surveys.