Up to four, one-character codes. Some maps have several types of relief. If more than one code applies, enter them left-justified in order of their importance to the map. If fewer than four codes apply, leave the remaining positions blank. No relief shown on map a Contours.
Relief is represented by contours.
Relief is represented by shading, usually of a single color. Relief is represented by gradient and bathymetric tints. Relief is represented by hachures, short lines which follow the direction of maximum slope. Relief is represented by form lines. Relief is represented by spot heights.