Most cover large, rugged areas, often including outflow channels, cratering, and "chaos terrain". They may be contrasted with the Planitia (e.g., Amazonis Planitia) and Mare (e.g., Mare Erythraeum), smoother regions of differing albedo.
Most cover extensive, rough areas, frequently encompassing outflow channels, craters, and "chaos terrain". They might be distinguished from Planitia (e.g., Amazonis Planitia) and Mare (e.g., Mare Erythraeum), smoother regions with varying albedo.