Data

The geologic map of Ophir and central Candor Chasmata is one of a series of 1:500,000 scale maps prepared for areas on Mars that are of particular scientific interest and may serve as potential future landing sites. This map is also part of a set that includes east Candor Chasma, west Candor Chasma, and Melas Chasma. The geologic interpretations are based dominantly on medium- and high-resolution

The geology for this map was compiled using Viking Orbiter images on 1:500,000- scale photomosaics of the Mars Transverse Mercator quadrangles -40262, -40267, and -40272. This map represents a detailed extension of regional geologic mapping of the east Hellas rim (Crown and others 1990, 1992) and is published at 1:1,000,000 scale. The map area is on the east rim of one of the largest impact struct

Since the 1970's, when the Mariner 9 spacecraft revealed the geologic diversity of Mars, the Chryse Planitia region has been noted for its immense outflow channels and chaotic terrain (McCauley and others, 1972; Sharp and Malin, 1975; Baker, 1982, chap. 3; Mars Channel Working Group, 1983). Various proposals for the origin of these features have been offered; most workers have favored a mechanism

The map area is in the Mangala-Memnonia region (fig. 1), which contains remarkably diverse geologic features and terrain types. Studies of the Mariner 9 images revealed the wide range of ages of the major rock units in this region; age assignments were based on the density of impact craters preserved on the various surfaces (Mutch and others, 1976, p. 56-60; Scott and Carr, 1978; Mutch and Morris,

This map is one in a series of 1:500,000-scale geologic maps prepared to investigate areas on Mars of high scientific interest. The quadrangle contains the source area for Mangala Valles, one of the largest outflow channel complexes on Mars (Sharp and Mali, 1975). Preliminary mapping by Masurksy and others (1986), Simbelman (1988), and Champlan and others (1989, 1991) showed that several episodes

Published geologic maps of the south polar region of Mars, made using either Mariner 9 (Condit and Soderblom, 1978) or Viking Orbiter (Tanaka and Scott, 1987) images, identified only layered deposits and polar ice within this map area. Layered deposits probably underlie all of the other units shown on this map. The residual polar ice cap, partial frost cover, and two low-albedo units are also mapp

Published geologic maps of south polar region of Mars have been based on either Mariner 9 (Condit Soderblom, 1978; Scott and Carr, 1978) or Viking Orbiter (Tanaka and Scott, 1987) images. The mapped extent of the southern layered deposits differs in many places on these maps and on our maps. These differences reflect the difficulty in accurately determining the location of the contact between the

Volcanoes are among the most imposing and geologically interesting features on Mars. Nearly 60 percent of the planets surface is covered by volcanic rocks dating from the Early Noachian to Late Amazonian Epochs (Tanaka and others, 1988). This map of the volcano Apollinaris Patera and surrounding area is one of a series of large-scale (1:500,000) geologic maps initiated by the National Aeronautics

The quadrangle is in the northern Maja Valles region on the west edge of the Chryse Planitia. This map is one in a sequence of three that also includes MTM 15057 and 20057. The sequence covers that part of the lower reaches of the Maja Valles that includes the transition from the higher Lunae Planum surface to the lower Chryse Planitia surface. The major interest in this quadrangle is the effects

The surface of the moon is heterogeneous. The differences from area to area of characteristic topographic forms and of physical properties such as albedo (reflectivity under full-Moon illumination) indicate that the materials underlying the surface vary from one area to another and that different processes have operated in the development of the surface. In lunar geologic mapping, areas are deline

The area of MC-28 is centered at the east edge of the Hellas Planitia (Hellas basin and surrounding plains) within densely cratered terrain that covers more than half the surface of Mars (Carr, 1973). The deepest part of the basin lies 4-5 km below the surface of the cratered terrain (Hanel and others, 1972). An irregular band of mountain and knobby material about the eastern margin of the basin

The Beethoven quadrangle is located in the equatorial region of Mercury, in the center of the imaged area. Most pictures of the quadrangle were obtained at high sun angles as the Mariner 10 spacecraft receded from the planet. Images in the northeastern part of the quadrangle are very poor to unusable. Another difficulty in mapping is the poor match in topographic bases between Beethoven and adjace