Geologic Map of the Sabine EB Region of the Moon

The Sabin EB region is a rolling plain which consists entirely of crater and mare materials. The areal density of craters, though variable within the region, is sufficiently high so that the craters are the dominant morphological feature. Crater morphology ranges from bright, sharp-rimmed craters to pan-shaped depressions. Superposition relations indicate that the bright-rimmed craters (unit br) are youngest and that such craters are degraded in time to shallow, subdued depressions (unit sr) and presumably to total destruction. It appears that the bright rim deposits, characteristics of the youngest craters, darken with time until their albedo is the same as that of the surrounding material (as in the unit dr). Degradation of crater rims probably is caused by superposed crater rims probably is caused by superposed impacts, burial by ejecta from more distant younger craters, and downslope movement of surficial materials. A few craters (unit d) have complex-upward walls which appear to have formed by inward slumping late in the degradation process.