Geological Mapping in the Canadian Shield: Implications for RADARSAT-2

摘要

Recent results have shown that RADARSAT-1 images have provided geologists with useful information in mapping structure and geomorphology and rock units in vegetated and non-vegetated terrains. In this paper, we evaluate the role of the additional capabilities planned for RADARSAT-2 for geological mapping in a typical Precambrian Shield terrain. Specifically, this involves the role of high resolution and polarimetric data for mapping outcrops and other geological features. For this evaluation, we have acquired two airborne high-resolution polarimetric SAR data set in the Madawaska Highlands area of Ontario. The areas are typical "Canadian Shield terrains" and consist of 10-30% Precambrian outcrops, variable thickness of drift cover and a dense to sparse forest cover. The imagery was acquired to simulate RADARSAT-2 Ultra Fine modes using the Environment Canada CV-580 C-band SAR system originally developed by CCRS. Our initial results show that in vegetated areas, the improved spatial resolution of RADARSAT-2 will be more useful for geological mapping than the polarization capability. However, we are finding that the polarimetric composites are providing additional details in lineament definition in some areas. The reason for this is not clearly understood.