Dating the martian surface Geologists use stratigraphic mapping to understand the evolution of planetary surfaces. 44 from Mars are the limited number of martian meteorites, i.e. the SNC meteorites. of the period of heavy bombardment marking the last stages of planetary accretion. Any water at shalthe south-east. The oldest Allan Hills meteorites were found close to the eastern edge and in the southeast of the main icefield. Among all Antarctic meteorites measured to date. All meteorites come from inside our solar system.
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According to Alavipanah study [ 6 ] the Lut Desert, particularly the yardangs region, is characterized by an extremely arid climate with excessive summer heat and an annual rainfall less than 50 mm. Method to study Surface Morphology of Meteorite In terrestrial environments, meteorites are subject to weathering processes that lead to the formation of secondary surface morphology and show external weathering of exposure meteorite to climate.
The rate and form of meteorite reshaping in continents is governed by the environmental condition such as climate, soil, and geomorphology.
H chondrites have high metal concentration which subsequently makes them prone to fragment during weathering. In this work, for studying surface morphology and surface alteration processes of meteorite, several parts of H5 should be considered that found in different environment such as sandy land or lee sidesalty land and lag gravel surface in southwestern Lut Desert in Kalut, these samples previously classified and described by some researchers [ 8 ].
Surface Morphology of Meteorite H5 Some pieces of meteorite were buried in the sand during aeolian processes and we were finding them after emerging by wind blowing sediments above them, they are the best preserved ones and show less exposure time to the air.
Some of these samples were placed in lee side and thus keep away from wind and water alternation. Most of the meteorites found in sandy land H5a keep their outer crust Figure 1but the most weathered parts were exposed to salt and groundwater in salty land H5c. Soil salts dissolved by water infiltrate into meteorite by capillary forces triggered by temperature fluctuations. So the most weathered meteorite as observed in salty land that expose to atmosphere and soil characteristics.
H5a meteorite with outer crust in sandy land. Fragments of H5c meteorite in salty land.
Geology of Mars - Wikipedia
Wind ablation can modify the surface of these meteorites. Most of these meteorites become ventifacts with flat, wind-abraded surfaces H5b Figure 3. These meteorites have a variety of wind-abraded surfaces ranging from surficial polishing to deep incision from late Pleistocene and Holocene sand grain saltation.
Fragments of H5b meteorite polished and abraded by wind. Results, Discussion and Conclusion Surface morphology of meteorites reveals physical surface alteration processes in the Lut Desert.
Most meteorites reveal their terrestrial environment on their surface. Surface morphology of meteorite depicts the effect of environmental condition on physical weathering of meteorite of Lut Desert. Major physical processes in desert depend on dry and hot climate and soil characteristics. In this article 3 main environments illustrate wind, salt and sand condition on physical surface of meteorite.
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Results of studying surface morphology of H5 meteorite in these three environments reveals meteorite has been very weakly altered and outer crust retained in sandy land. Tall volcanoes appear white.
Where do meteorites come from?
Valles Marineris blue is the long gash-like feature to the right. The Elysium province is at the upper right edge.Birth of the Moon
Areas north of the dichotomy boundary appear as shades of blue on both maps. The northern and southern hemispheres of Mars are strikingly different from each other in topography and physiography. This dichotomy is a fundamental global geologic feature of the planet. Simply stated, the northern part of the planet is an enormous topographic depression. In contrast, the lowlands north of the dichotomy boundary have few large craters, are very smooth and flat, and have other features indicating that extensive resurfacing has occurred since the southern highlands formed.
The third distinction between the two hemispheres is in crustal thickness. The origin and age of the hemispheric dichotomy are still debated.
Hypotheses of origin generally fall into two categories: A new theory based on the Southern Polar Giant Impact  and validated by the discovery of twelve hemispherical alignments  shows that exogenic theories appear to be stronger than endogenic theories and that Mars never had plate tectonics   that could modify the dichotomy. Laser altimeter and radar sounding data from orbiting spacecraft have identified a large number of basin-sized structures previously hidden in visual images.
Called quasi-circular depressions QCDsthese features likely represent derelict impact craters from the period of heavy bombardment that are now covered by a veneer of younger deposits.
Crater counting studies of QCDs suggest that the underlying surface in the northern hemisphere is at least as old as the oldest exposed crust in the southern highlands. The vast Alba Mons formerly Alba Patera occupies the northern part of the region.
The huge shield volcano Olympus Mons lies off the main bulge, at the western edge of the province. As a result, immense extensional fractures grabens and rift valleys radiate outward from Tharsis, extending halfway around the planet. The Elysium volcanic complex is about 2, kilometers in diameter and consists of three main volcanoes, Elysium MonsHecates Tholusand Albor Tholus.
The Elysium group of volcanoes is thought to be somewhat different from the Tharsis Montes, in that development of the former involved both lavas and pyroclastics. The largest one that is readily visible is the Hellas basin located in the southern hemisphere. Ancient, low-relief volcanic constructs highland paterae are located on the northeastern and southwestern portions of the rim. The basin floor contains thick, structurally complex sedimentary deposits that have a long geologic history of deposition, erosion, and internal deformation.
The mountains in the southern portion of the rim, Charitum Montesmay have been eroded by valley glaciers and ice sheets at some point in Mars's history.