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Research about Mars

Source-linked reports with geographic coverage including Mars.

At least 397 records · Page 22Linked to original sources
USGS1979

Geologic map of the Memnonia Quadrangle of Mars

The Memnonia quadrangle lies astride the boundary between heavily cratered and sparsely crater ed hemispheres of Mars ( Carr and others, 1973). Densely cratered terrain occurs in the southwestern part of the quadrangle. Strips of plains material bound the cratered terrain in both the northern and eastern parts of the quadrangle . There is approximately 3 km of relief across the quadrangle, with the highest elevations in the eastern part. Plains materials of this region are situated along the lower slopes of the Tharsis Montes, which con tinue to rise in elevation eastward in t o the adjacent Pheo nicis Lacus and Tharsis quadrangle. There is little correlation between terrain types and elevation within the Mamnonia quadrangle. In particular , the boundary between cratered terrain and plains for the most part is not marked by any prominent change in elevation .

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USGS1979

Geologic map of the Phaethontis Quadrangle of Mars

The Phaethontis quadrangle of Mars is dominated by densely cratered uplands and plateaus which form some of the oldest surfaces on the planet. Extensive low-lying areas within the cratered terrains, including the floors of the large craters , are covered to different degrees by plains-forming material. The youngest plains unit surround Tharsis Montes to the north. Various erosional processes, including eolian scour and possibly scarp retreat through volatile-release sapping and mass wasting, producing several distinctive physiographic features: knob and mesa terrains, plains and small knobs, and plateaus dissected by furrows, steep walled gorges, and pits.

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USGS1979

Geologic map of the Arcadia Quadrangle of Mars

The Arcadia quadrangle of Mars contains three distinct geological provinces: (1) the 1000-km-diameter shield field volcano of Alba Patera, which occupies the southwestern quadrant ; (2) the complex T empe province, which comprises a number of younger volcanic and sedimentary blanket deposits over an ancient, highly cratered crust forming a plateau in the southwestern quadrant ; and (3) a plains province, consisting of northern wind-swept , c ratered plains and some younger subpolar deposits in the northeast corner of the quadrangle, plus less cratered plains surrounding much of the T empe and Alba regions. The plateau, informally named the Tempe Plateau and part of the proposed forma l term Tempe Terra, is separated from the main regions of cratered martian highlands to the south by Kasei Vallis , appearing at the extreme southeast corner of the map, which slopes northeastward onto Chryse Planitia.

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USGS1979

Atlas of Mars: the 1:5,000,000 map series

This atlas comprises small-scale maps and photomosaics covering the entire surface of the planet Mars. The cartographic contents are reduced-scale versions of the 1:5,000,000 topographic series of 30 quadrangles compiled by the U.S. Geological Survey in cooperation with the National Aeronautics and Space Administration (NASA).

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USGS1978

Geologic map of the Casius Quadrangle of Mars

Geologic units of the martian surface are subdivided on the basis of surface morphology, albedo, and crater distribution and are placed in a stratigraphic sequence following principles of superposition, crosscutting relations, and, to a degree, crater density. The Casius quadrangle (30˚ N to 65˚ N lat; 240˚ W to 300˚ 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 plains which forms an incomplete annulus around the north polar region, 2) smooth lowland plains of Utopia Planitia across the central and southeastern part of the map, 3) mountainous terrain, in the Nilosyrtis Mensae region south of the lowland plains, consisting of distinct mountains with hummocky surfaces, and 4) cratered plateau in the southwest part of the map, forming the northern part of the large complex cratered region in the mid-latitudes of Mars. In the Casius quadrangle, the cratered plateau is broken by a set of linear to curved parallel-sided canyons on its northern margin.

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USGS1978

Geologic map of the Mare Australe area of Mars

The south polar region of Mars is among the most geologically diverse on the planet. The areas is within the heavily cratered hemisphere of Mars bu t is distinguished by a variety of younger, regionally extensive deposits and a n a ssemblage of unique erosional forms. The spectrum of units varies from the oldest to the youngest on the planet. The oldest unit, typif ying t h e cratered hemisphere, is the material of ancient large craters, most of which have undergone advanced degradation. These ancient crater materials are overlain by a variety of regional deposits, including extensive intercrater debris blankets, r i dged volcanic flows, and massive eolian deposits that eroded to form complex cliff-rimmed pits. In the central zone of the polar region, south of roughly 75 ˚ S., these depositional units are, in turn, unconformably overlain by a t remendous sedimentary complex 1,500-2,000 km in diameter, consisting of 40 or more regularly spaced horizontal starta . Each stratum retains apparently uniform thickness (several tons of meters) over hundreds of kilometers; erosional unconformities between starta have not as yet been identified. Resting on the uppermost surface of this layered terrain is the perm anent residual polar ice cap. This complex stratigraphic record may ultimately hold the keys t o the initial atmospheric evolution, climatological fluctuations, and the history, budget, and mobility of wate r on the planet.

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USGS1978

Geologic map of the Aeolis Quadrangle of Mars

Two principal physiographic provinces of Mars are represented in the Aeolis quadrangle: (1) Elysium Plan itia 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 roughly primitive terrain that extends to polar deposits around the southern ice cap (Condit and Soderblom, 1978: Scott and Carr , 1978). These two terrains are separated by an irregular discont inuous northwest-trending scarp that becomes less conspicuous and more segmented toward the east part of the ma p area. Two large channels transect the highlands; they widen northward downslope and have other features cha racteristic of terrestrial river beds . However, now fans or deltaic forms are visible at their mouths and their floors merge with the plains. One large shield volcano, Apollinaris Patera, projects above the plains adjacent to the highlands in the northeast part of the quadrangle. More than 4 km of relief occur across the region from the high plateau in the south and west, downslope northward to plains.

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USGS1978

Geologic map of the Coprates Quadrangle of Mars

The Coprates quadrangle lies to the east of the Tharsis volcanic complex and the Noctis Labyrinthus tectonic complex. To the north are the plains of Lunae Planum, to the east the vast patches of chaotic terrain and the large sinuous channels that trend northward to the Chryse Planitia. On the southwest is the Thaumasia Fossae region of the tectonically deformed cratered terrain, to the southeast, the Argyre Basin, the best preserve of the ancient Martian impact basins. The geology of the Coprates quadrangle is dominated by the Valles Marineris chasma system, which stretches in a east-southeast direction for about 2,500 km across the quadrangle. Its maximum width is about 600 km form the north rim of Ophir Chasma to the south rim of Melas Chasma. The terminus of Valles Marineris at the eastern edge of the map is about 500 km wide in the north-south direction. Individual segments of the chasma system are 100 to 150 km wide and 2 to 4 km deep. Much of the geology described here is common to other regions of Mars and has been discussed previously not only in summary papers but by other quadrangle mappers. Preliminary attempts at the regional geology of Mars have been made by McCauley and others (1972) and Carr and others (1973). Those units and features common to other parts of Mars are discussed first. The focus of this discussion is on Valles Marineris and those features that are unique to this quadrangle.

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USGS1978

Morphology of chasma walls, Mars

The landforms developed on the walls of the Valles Marineris system of chasmas are of three major types, which are locally transitional. The most common type is composed of steep spurs and gullies. The dominant process in the formation or modification of this type appears to be the downslope movement of. material under the influence of gravity, resulting in the accumulation of extensive talus deposits. The type is morphologically similar to high, steep terrestrial scarps in desert or alpine environments. The second morphologic type consists of walls dissected by tributary canyons with characteristic V-shaped cross profiles and blunt canyon heads that locally contain lobate deposits. The tributary canyons may be relict features of the time, when the existence of running water was possible on the surface of Mars. The third morphologic type consists of landslide scars forming broad curved or straight recessed sections of chasma wall. This type is accompanied by landslide deposits that form hummocky floors at the base of the recessed sections. The landslides developed at the expense of other wall morphologies. Chains of rimless depressions and craters that parallel the main structural trends of the chasmas are best interpreted as collapse holes. The origin of the chasmas on Mars is conjectural and may have been structural (grabens), but, on the basis of morphologic studies of their walls, it is suggested that most of the present wall configuration is the result of erosional scarp retreat, where erosion follows preestablished structural planes of weakness.

Journal of Research of the U.S. Geological Survey↗
USGS1977

Geologic map of the Eridania Quadrangle of Mars

The Eridania quadrangle is located within the densely cratered terrain of the southern hemisphere of Mars, east of the large circular Hellas Basin. The areas contain three distinct physiographic provinces that div ide the quadrangle into latitud in al belts. The northern part of the quadrangle is dominated by cratered upland plateau, the central part by plains, the southern part by a mottled surface of rugged topography and a high density of craters subdued by erosion. In general, the oldest geologic unit occurs in the upland terrain, the youngest in the central lowlands. Large contrast in albedo were observed on Mars from Earth long before Mariner spaceflight missions. The most conspic uous of these features within the quadrangle are areas of low albedo in the north and in the south that corresponds to the two main belts of high-relief terrain. The intervening region of high albedo corresponds to the central plains belt, also an area of recurrent seasonal frost. The southern polar cap extends to about 50 ˚ S lat and includes all of the southern belt of high relief.

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USGS1977

Geologic map of the Iapygia Quadrangle of Mars

The Iaygia quadrangle, in the equatorial region of Mars just north of the Hellas basin, is mainly ancient, hilly, and cratered upland terrain. The southern one-third of the quadrangle is dominated by mountains and knobby materials representing mountains of pre-Hellas material and material related to the Hellas basin and mappable in a 500-km-wide zone circumjacent to it. The northeast quadrant of the quadrangle contains two large arcuate structural scarps and moderately low-albedo mountai n material and knobby deposits, both associated with formation of the Isidis basin (Meyer and Grolier, 1977). The major part of the Iapygia quadrangle is mapped as hilly and cratered upland materials units with subordinate various plains deposits. Although the southern rim of the Syrtis Major basin coincides with the northern margin of the quadrangle along the equator from 285 ˚ to 295 ˚ W., no structural features or ejecta associated with the basin have been identified in either the Iaypgia or Syrtis Major (MC-13) quadrangle. A dominant feature of the landscape with Iaypgia is the 475-km-diameter basin-crater Huygens, which shows subtle evidence of having an inner ring structure ( Wilhelms , 1973). A second basin-sized crater , Schroeter (265-km-diameter), shares its northern rim with the Syrtis Major quadrangle (MC-13) and has a more distinct inner ring structure than Huygens.

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USGS1977

Geologic map of the Noachis Quadrangle of Mars

The Noachis quadrangle is in the anc i ent cratered highlands of Mars. Craters dominate the surface of the planet in this area; most are of impact origin, some are of volcanic, origin, and some are of undetermined origin. Martian craters are I general similar in morphology of lunar craters but are more degraded. Analogous morphologies and size-frequency distributions of lunar and Martian craters indicate that both populations are mostly of impact or i gin (McCauley and others, 1972). Martian 10 pictures of Mercury suggest similar t rends on that planet, a further indication that the crating process was exogen ous.

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USGS1977

Geologic map of the Syrtis Major Quadrangle of Mars

The Syrtis Major quadrangle is located in the equatorial belt of Mars across the boundary between the cratered plateau region to the south and west and the northern lowland plains. The cratered plateau is part of the northern extension of cratered highlands, which generally stands at altitudes greater than 4 km. The southeastern part of the quadrangle is dominated by eastward-sloping plains on the flood of Syrtis Major and Isidis Planitia. Total relief in the quadrangle is greater than 6 km over a latitudinal distance of 2,000 km, corresponding to a regional slope of 0.6 degree in east-northeast direction.

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USGS1977

Geologic map of the Arabia Quadrangle of Mars

The Arabia quadrangle is located in the northern hemisphere of Mars; it extends 30 ˚ N. from the equator and 45˚ 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 o f Mars ( Carr and others, 1973). Crater density in the Arabia quadrangle is similar to the heavily cratered regions located south of the equator owing to inclination of the great circle division between heavily and less cratered Martian terrains ( Soberblom and others (1974). Non e of the large prominent telescopically defined Martian surface markings dominate the Arabia quadrangle, although the northern tip of Meridiani Sinus projects slightly into the extreme southwest corner. The topographic map of Mars (U. S. Geol. Survey, 1976) indicates that elevations in the Araba quadrangle rise toward the northeast. The entire region lacks high relief.

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USGS1977

Planimetric Martian triangulations

Narrow-angle photographs, which have severe drawbacks for stereophotogrammetry, have advantages for simple plane triangulations. Rectified narrow-angle pictures corrected for map projection effects can be combined in the map plane in relatively accurate planimetric triangulations. Provided the strict precepts of least squares are not followed, these triangulations can incorporate considerable overdetermination without increase in the labor of solving the equations. These plane triangulations have been used successfully in the cartography of Mars and are illustrated here by a triangulation of the environs of the prime Martian landing site.

Photogrammetric Engineering and Remote Sensing↗
USGS1976

Preliminary results from the Viking orbiter imaging experiment

During its first 30 orbits around Mars, the Viking orbiter took approximately 1000 photographic frames of the surface of Mars with resolutions that ranged from 100 meters to a little more than 1 kilometer. Most were of potential landing sites in Chryse Planitia and Cydonia and near Capri Chasma. Contiguous high-resolution coverage in these areas has led to an increased understanding of surface processes, particularly cratering, fluvial, and mass-wasting phenomena. Most of the surfaces examined appear relatively old, channel features abound, and a variety of features suggestive of permafrost have been identified. The ejecta patterns around large craters imply that fluid flow of ejecta occurred after ballistic deposition. Variable features in the photographed area appear to have changed little since observed 5 years ago from Mariner 9. A variety of atmospheric phenomena were observed, including diffuse morning hazes, both stationary and moving discrete white clouds, and wave clouds covering extensive areas.

Science↗
USGS1976

The surface of Mars: The view from the Viking 1 lander

The first photographs ever returned from the surface of Mars were obtained by two facsimile cameras aboard the Viking 1 lander, including black-and-white and color, 0.12° and 0.04° resolution, and monoscopic and stereoscopic images. The surface, on the western slopes of Chryse Planitia, is a boulder-strewn deeply reddish desert, with distant eminences—some of which may be the rims of impact craters—surmounted by a pink sky. Both impact and aeolian processes are evident. After dissipation of a small dust cloud stirred by the landing maneuvers, no subsequent signs of movement were detected on the landscape, and nothing has been observed that is indicative of macroscopic biology at this time and place.

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