Data

This map sheet is one of a series covering that part of the surface of Mercury that was illuminated during the Mariner 10 encounters. Planimetric control is provided by photogrammetric triangulation using Mariner 10 pictures (Davies and Batson, 1975). Discrepancies between images in the base mosaic and computed control-point positions appear to be less than 5 km. No attempt was made to resolve dis

The Arabia quadrangle is located in the northern hemisphere of Mars; it extends 30 degrees N. from the equator and 45 degrees E. from the prime meridian. It is within the area of unmantled terrain defined by Soberblom and others (1973) and the planet-encircling band of old cratered deposits shown on the preliminary geologic map of Mars (Carr and others, 1973). Crater density in the Arabia quadrang

Mars presents two different terrains, a highly cratered surface that lies mostly in the southern hemisphere and sparsely cratered plains that lie mostly in the northern hemisphere. The cause of the dichotomy is a still unsolved fundamental problem of Martian geology, analogous to the problem of continents and ocean basins in terrestrial geology. The present features of the plains in particular r

Two principal physiographic province of Mars are represented in the Aeolis quadrangle: (1) Elysium Planitia in the north is part of a broad planet-encircling belt of relatively young lowland plains, and (2) cratered highlands in the south consist of rough primitive terrain that extends to polar deposits around the southern ice cap (Condit and Soderblom, 1978; Scott and Carr, 1978). These two terr

The brightly rayed crater Coperincus, one of the most familiar features of the Moon served as the type example of an impact crater in Shoemaker's (1962) classic analysis. This map shows the geology of the crater as interpreted in photographs taken by Lunar Orbiter V. A geologic map at 1:1,000,000 scale showing the regional setting of Copernicus and the extent of the rim deposits and satellite cra

The Casius quadrangle (30 degrees N to 65 degrees N lat; 240 degrees W to 300 degrees W long) is one of the northern tier of Lambert conformal sheets of the Mars Atlas. It consists of four distinctive physiographic regions: 1) part of the northern cratered plain which forms an incomplete annulus around the north polar region, 2) smooth lowland plains of Utopia Planitia across the central and south

The east Mangala Valles area merits detailed geologic study because it contains several small channels whose ages can be determined relative to geologic units that range in age from early (Noachian) to late (Amazonian) periods of Martian history. Because small channels are of three ages and geomorphic types, their study increases our understanding of the continuity of fluvial processes in the evol

The Aristoteles quadrangle, located on the northeastern periphery of the Imbrium basin on the near side of the Moon, consist of four physiographic provinces: a northern mountainous belt, chiefly of lineated crater rims and other lineated terra; a middle-northern belt covered by mare material of Mare Frigoris; and a southern belt composed of mountainous material of diverse characteristics. The crat

The application of stratigraphic and structural principles to geologic mapping of the Moon from telescopic photographs has been discussed by Shoemaker (1962) and Shoemaker and Hackman (1962). Major geologic units are recognized by regional topographic and albedo differences. Pictures returned by Ranger, Surveyor, and Lunar Orbiter spacecraft show that a fragmental regolith, presumably produced by

The Grimaldi quadrangle lies at the southwest margin of Oceanus Procellarum about 1,000 km east of Orientale, the youngest of the lunar multi-ringed basins. The distal ends of the ejecta blanket surrounding the Orientale basin partly covers the western third of the quadrangle. The relatively small, two-ring Grimaldi basin is in the northwest corner of the quadrangle, and the Humorum basin lies abo

The Mare Tyrrhenum quadrangle is bounded by lat 0 degrees and 30 degrees S. and long 225 degrees W. and 270 degrees W. The central part of the quadrangle is dominated by Tyrrhena Patera, a large shield volcano, and associated low-albedo ridged plains that probably are basaltic lava flows similar to the lunar maria. The western, northern, and eastern margins of the quadrangle are located in crater

The Tharsis quadrangle lies within the sparsely cratered hemisphere (Carr and others, 1973) of Mars. Its geology is dominated by young volcanic features, including both circular constructs and lava plains; little evidence of primitive densely cratered terrain remains. Included are three of the four largest shield volcanoes in the Tharsis province, Olympus Mons, Ascraeus Mons, and Pavonis Mons, t