Filters: Contacts: D. H. Scott (X)
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Volcanoes are among the most imposing and geologically interesting features on Mars. Nearly 60 percent of the planet’s 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 and Space Administration to investigate areas of particular scientific interest. The areas selected for mapping contain candidate landing sites for future sample-return missions to Mars (fig. 1).
These geologic and topographic maps show a basin in the Elysium region of Mars that is thought to have been the site of a large paleolake during the most recent period (Amazonian) in Mars' history (Scott and Chapman, 1991b). The basin, referred to as the Elysium basin, extends for more than 2,000 km across the lowland plains. It is important, not only geologically, but because the amount, location, and duration of liquid water that it may have contained would have been critical factors governing the possible origin and survival of life on Mars.
Although geologic mapping fo the Moon has its own techniques and problems, systematic observation and the application of established geological principles have allowed the materials and structures of its surface to be delineated and classified into units (Shoemaker and Hackman 1962; McCauley 1967; Wilhelms, 1970). Most of these units are material entities similar to terrestrial rock-stratigraphic units and have been arranged in chronological sequence to form a lunar stratigraphic column. Relative ages are determined by superposition, embayment and cross cutting relations, and by density of superposed craters and degree of topographic freshness (Wilhelms 1970). In addition, crater morphologies are believed to be...
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 adjacent quadrangles. Mismatches are especially common along the borders with the Kuiper and Discovery quadrangles to the east and southeast.
The Elysium quadrangle includes part of the vast, relatively low and featureless plains that encircle the subpolar region of Mars immediately north of the more elevated and cratered equatorial belt. The plains are interrupted in the northwest by two large volcanoes, second only in size and youthful appearance to some of the large constructs that form the planet’s most prominent volcanic center in the Tharsis region several thousand kilometres to the east (Carr, 1975). The large irregularity shaped crater Orcus Patera, at the east boundary of the map, closely resembles the lunar crater Schiller but is more than twice as long. A band of knobby, relatively old terrain extends in a broad arc northeastward through the...
This map is one in a series of 1:500,000-scale geologic maps initiated by NASA to investigate areas of particular scientific interest on Mars. The north Kasei Valles area merits detailed geologic study because it contains part of a large channel system whose age can be determined relative to geologic units that range in age from early intermediate (Early Hesperian) to the very late (Late Amazonian) periods of Martian history. Also, many geomorphic features in the map area suggest changes in water level and multiple erosional events associated with the Kasei Valles system. Later erosional events are indicative of spring sapping; small-scale, ground-water runoff; and water-mobilized debris flow. Therefore, this large-scale...
The Valles Marineris region lies east of Tharsis Montes (which extend from lat 12˚ to 16˚., long 101˚ to 125˚). Part of the region is in the midst of a vast plateau bounded on the west and east by Claritas and Nectaris Fossae, respectively; the remainder extends farther east into southern Xanthe Terr and western Margaritifer Terra. Channel trends, stereophotogrammetry, and radar altimetery indicate that the surface north and east of the canyons slopes toward Chryse Planitia (centered at about lat 25˚ N., long 45˚). Within the broad Valles Marineris region, three distinct physiographic provinces are recognized (fig. 1): (1) the Noctis Labyrithus province, consisting of a high plateau cut by a network of structurally...
The Eudoxus quadrangle is in the northeastern part of the Moon's nearside hemisphere. It is bordered on the west by Montes Caucasus, which form part of the main rim of the multi-ringed Imbrium basin (Hartmann and Kuiper, 1962), and on the southside by Mare Serenitatis, which occupies another large multi-ringed basin. South and East of the prominent crater Eudoxus elevations decrease and the rugged highland terrain becomes more subdued and covered by mare materials in the Serenitatis basin, Lucas Somniorum and Lucas Mortis.
The region centered at Elysium Mons contains the second largest volcanic complex on Mars, surpassed in size by only the Tharsis complex. The Elysium region also has been a center of tectonic, fluvial, and mass-wasting activity. After degredation of ancient cratered terrain within the northern lowlands, volcanic rocks erupted from the Elysium Mons, Hecates Tholus, and Albor Tholus in Elysium Planitia. The volcanic activity was associated with episodes of channel formation, faulting, and apparent volcano/ground-ice modifications of some areas.
The Rumker quadrangle, in the northwest quadrant of the Moon, is adjacent to the western rim of the multi-ring Imbrium basin and to Sinus Iridum, a large (220 km diameter) mare-filled crater. Both of these great depressions were probably formed by impact, as indicated here and elsewhere on the Moon by the characteristic form, distribution, and texture of surrounding materials and structures. The Imbrium basin and Iridium crater were filled by mare materials during the Imbrium and Eratosthenian Periods. In this quadrangle, the widespread ejecta blanket of the Imbrium basin, as well as the basin's concentric ridges and mountian rings, has largely been buried by terra materials of mixed origin and by ejecta from Iridum...
Kasei Valles (fig. 1) make up the largest system of outflow channels on Mars and were a major contributor of water to Chryse Planitia. The walls and floors of the Kasei channels are terraced and grooved, closely resembling the channeled scablands of eastern Washington State that were formed by catastrophic floods probably lasting no more than a few days (Baker and Milton, 1974; Baker and Kochel, 1979). Evidence obtained from previous geologic mapping of parts of Kasei Valles (Chapman and Scott, 1989) was not conclusive as to whether water levels varied markedly during single flood and erosional event or whether flooding was episodic and marked by intermittent periods of scouring. This problem – whether one or several...
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