| Abstract | Our research presents some guidelines for the selection of the various RADARSAT-1 incidence angles for geological applications. The study areas were selected to represent different terrain types and
surfaces both in Canada and around the world. The terrain types represented include: high relief, rugged, forested, mountainous environments (Hope, BC; China), moderate to high relief environments (Cape Breton Highlands, N.S.), moderate relief
environments, glaciated, forested Precambrian Shield terrains (Geraldton, ON; Sudbury, ON; Whitecourt, AB), and low relief environments, partly vegetated, flat to rolling prairie landscapes (Morden, MN; Jordan). Our results show that the selection of
the most useful RADARSAT-1 viewing geometry is application and site specific. Significant difference exists in the interpretability of geological structure, lithological units, landform and terrain types depending on the incidence angle chosen for
image acquisition. In low relief environments, small incidence angles (10 to 25 degrees from vertical) will produce the maximum relief enhancement, but larger incidence angles (25 to 59 degrees) will also result in acceptable terrain rendition by
increasing the terrain textural contrasts. In moderate relief environments, small to intermediate incidence angles (20 to 35 degrees) are suitable since they produce a good topographical enhancement. In high relief environments, intermediate to large
incidence angles (35 to 59 degrees) are recommended to reduce geometric distortion and minimise shadow effects. |