In this study, a UAV GEM Airbird magnetometer system was used, which consists of lightweight potassium magne- tic sensor with a sensitivity ~0.001 nT/ Hz, GPS, laser altimeter, EMU sensor and data acquisition and control unit. In addition, real-time data transfer through a radio link was set up to receive data from the UAV magnetometer for dynam- ic data-logging and tracking. A ground magnetometer was used as the base station for diurnal corrections, which had time synchronization with GPS. It was observed that the intensity of contours trend in the E–W direction coinciding with the strike of the dolerite dyke. The contour pattern clearly reveals the dyke and adjacent granitic terrain. The contours are dense with high magnetic gradient over the dyke, while they are diffuse away from the dyke. The dyke is well reflected in the central part of the contour map derived from the UAV magnetic data of the study area. The results clearly distinguish the mafic dolerite dyke and granitic terrain in the test area. The present study has successfully demonstrated the capability of UAV-Magnetic survey, which is cost effective, faster and reliable.
Figure: magnetic map produced
G. Ashok Babu, G. Vamsi Krishna, V. M. Tiwari, R. Antony, C. S. Suraj, K. T. Vikas, P. V. S. Murthy; Current Science, Vol. 119, No. 4, 25 August 2020