This figure is a map of Mars. The map is rainbow colour coded from red to violet. Violet and blue colours represent low detection of silicates. Orange and red colours show high detection of silicates. The map is roughly divided into thirds from top to bottom (north to south). The top third is mainly grey, indicating no data was collected there. The next third (to the south) is mainly blue, showing low levels of silicates, with some green areas to the south. The next third south blue and green, indicating higher levels of silicates. The south polar region is coloured grey, indicating no data was collected there.