Geologic map of the Rima Hyginus region of the Moon

The Rima Hyginus region lies within the Mare Vaporum quadrangle (LAC 59), 7 degrees from the center of the lunar earthside hemisphere, near several large impact basins. The Rima Hyginus region occupies a broad structural trough concentric with the Imbrium basin, which has especially controlled the geology of the area, Plains-forming materials cover most of the region, except for a belt of hilly terrain with about 600m of relief, to the north, and some isolated hills to the west. Numerous linear grabens and a chain of endogenic craters are the prominent structures; the region includes only three craters larger than 5 km in diameter.