Stratigraphy
Three widespread units are recognized within the Victoria quadrangle. These are, from oldest to youngest, intercrater plains material, intermediate plains material, and smooth plains material. In addition, central peak, floor, rim, and ejecta materials related to the numerous craters and basins larger than about 20 km in diameter are mapped. The simplicity of the stratigraphic scheme is at least in part due to deficiencies in the data base; the history of plains formation almost certainly is more complex than our threefold division indicates, but we were not able to define consistent criteria of albedo, texture, and cratering for more than three plains units because of the highly variable quality of available pictures.
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