Helicopter-borne magnetic and radiometric geophysical survey in Dividalen, Målselv municipality, Troms county

Abstract

NGU conducted an airborne magnetic and radiometric survey in the Dividalen area in September 2013 and October 2014 as a part of the MINN project (Mineral resources in Northern Norway).This report described and documents the aquisition, processing and visualization of recorded datasets. The geophysical survey results resported herein are 2014 line km, covering an area of 403 km2.A Scintrex CS-3 magnetometer in a towed bird and a 1024 channels RSX-5 spectrometer installed under the helicopter belly was used for data acquisition.The survey was flown with 200 m line spacing, line direction 28 dgrees. (NNE to SSW) and average speed 83 km\/h. The average terrain clearance was 75 m for the bird and 90 m for the spectrometer. Collected data were processed at NGU using Geosoft Oasis Montaj software. Raw total magnetid field data were corrected for diurnal variation and levelled using standard micro-levelling algorithm.Radiometric data were processes using standard procedures recommended by International Atomic Energy Association.Data were gridded with the cell size of 50 x 50 m and presented as a shaded relief maps at the scale of 1:50 000.