Geological mapping in Melville Peninsula, Northwest Territories, Canada using multi-source remote sensing and geophysical data

Abstract

A feasibility study has been initiated to use multispectral LANDSAT TM and geophysical data to delineate geological patterns as an aid to geological field mapping in Arctic regions in Canada. The Hall Lake area in Melville peninsula, Northwest Territories has been chosen for this study, because the area has little vegetation, relatively large areas of unweathered rock outcrops and a geological map covering a part of the area has been recently published. In addition to seven bands of TM, two airborne geophysical surveys, radiometric (four bands: U, Th, K and total exposure rate) and aeromagnetic data have been interpolated and geometrically registered with TM imagery. Ground gravity survey data have also been incorporated into the data set. Two subareas in which geological field mapping has been completed, were selected to test multivariate discriminant analysis procedure to characterize the geological units based on the TM and geophysical data. Multivariate discriminant analysis was applied to each one of the subareas as a training, then the classification results were then used to predict the geological units in the other subarea. Although discriminant models have adequately characterized the geological units from the TM and geophysical data within each training area, the prediction of geological units (which are mappable, but physically inhomogeneous geological abstractions) was not satisfactory.