(RLC-15) Geologic map of the Alphonsus GA region of the moon

This map is one of a series prepared from photographs transmitted by Ranger IX (Jet Propulsion Lab., 1966., pls. A56-A58, B70-B82). It depicts the geology of some 724 sq km in the northeast part of the floor of Alphonsus (diameter about 115 km), a typical flat-floored old terra crater or basin with subdued rim. Similar basins abound in the south-central tarrae of the visible hemisphere and on the far side of the Moon. Alphonsus is of particular interest, however, because of a well-developed interior rille system and associated dark-halo craters.