Classroom-sized geophysical experiments: magnetic surveying using modern smartphone devices

Abstract

Modern mobile devices (i.e. smartphones and tablet computers) are widespread, everyday tools, which are equipped with a variety of sensors including three-axis magnetometers. Here, we investigate the feasibility and the potential of using such mobile devices to mimic geophysical experiments in the classroom in a table-top setup. We focus on magnetic surveying and present a basic setup of a table-top experiment for collecting three-component magnetic data across well-defined source bodies and structures. Our results demonstrate that the quality of the recorded data is sufficient to address a number of important basic concepts in the magnetic method. The shown examples cover the analysis of magnetic data recorded across different kinds of dipole sources, thus illustrating the complexity of magnetic anomalies. In addition, we analyze the horizontal resolution capabilities using a pair of dipole sources placed at different horizontal distances to each other. Furthermore, we demonstrate that magnetic data recorded with a mobile device can even be used to introduce filtering, transformation, and inversion approaches as they are typically used when processing magnetic data sets recorded for real-world field applications. Thus, we conclude that such table-top experiments represent an easy-to-implement experimental procedure (as student exercise or classroom demonstration) and can provide first hands-on experience in the basic principles of magnetic surveying including the fundamentals of data acquisition, analysis and processing, as well as data evaluation and interpretation.

Linear Quadrupole Magnetic Field Measured with a Smartphone

“…Mobile devices can provide meaningful assistance to users in their work, study, and entertainment. They have been widely used in recent years within the process of instruction in different disciplinary fields, [4][5][6][7][8][9][10][11][12][13][14] although the effects on learning and the purpose given to them in the classroom are still being studied. Furthermore, smartphones are becoming the data recorders of portable physics laboratories for a variety of measurements in astronomy, mechanics, thermodynamics, electromagnetism, and optics among others, either using the internal sensors of cell phones or diverse applications.…”