Oudemans is a crater on

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...

, approximately 90 kilometers in diameter, named after Dutch astronomer Jean Abraham Chrétien Oudemans (1827–1906).

Description

Oudemans crater is an example of very pristine morphology since small features in its ejecta and on its floor are preserved. Being young, it does not display water erosion on its rim. Unlike some craters, Oudemans crater does not have alluvial fans on its floor. In places, its rim has a terrace. It is located in the Phoenicis Lacus quadrangle at 10.0 deg S, 92.1 deg W. This location puts it near the intersection of

Noctis Labyrinthus Noctis Labyrinthus () is a region of Mars located in the Phoenicis Lacus quadrangle, between Valles Marineris and the Tharsis upland. The region is notable for its maze-like system of deep, steep-walled valleys. The valleys and canyons of this ...

and the

Ius Chasma Ius Chasma is a large canyon in the Coprates quadrangle of Mars at 7° south latitude and 85.8° west longitude. It is about 938 km long and was named after a classical albedo feature name. Valles Marineris Canyon System Ius Chasma is a ...

of the

Valles Marineris Valles Marineris (; Latin for '' Mariner Valleys'', named after the ''Mariner 9'' Mars orbiter of 1971–72 which discovered it) is a system of canyons that runs along the Martian surface east of the Tharsis region. At more than long, wide and ...

rift system. It is approximately 90 km wide, indicating it was caused by a meteorite 4.5 km in diameter. Nick Hoffman proposes that this might be the trigger that caused the formation of the flow deposits on the east end of the Valles Marineris System. He proposes that the impact heated up subsurface

carbon dioxide Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is trans ...

permafrost causing explosive decompression that flooded down the Valles Marineris into the Northern Plains of Mars.Hoffman, Nick; White Mars: A New Model for Mars’ Surface and Atmosphere Based on CO₂; Academic Press; 2000. The central uplift of Oudemans exposes layered rock that may be sedimentary.HiRISE , Oudemans Crater Central Uplift: A Sample of Well-Preserved Layering Excavated from Kilometers Below (PSP_001602_1700)
/ref> Layered rock exposed in the central uplifts are common in terrestrial impact structures, and there is abundant layering exposed in the nearby Valles Marineris canyon system suggesting that layered deposits extend throughout the region. Oudemans' layers are from as deep or deeper than those exposed in Valles Marineris. A comparison of the layers in Valles Marineris and in the Oudemans central uplift may prove that they are similar rock types that share the same origin. Three other craters in the area,

Martin Martin may refer to: Places * Martin City (disambiguation) * Martin County (disambiguation) * Martin Township (disambiguation) Antarctica * Martin Peninsula, Marie Byrd Land * Port Martin, Adelie Land * Point Martin, South Orkney Islands Austr ...

(21.2°S, 290.7°E), Mazamba (27.3°S, 290.2°E) and a yet unnamed crater (28.4°S, 305°E) also possess finely layered materials in their central uplift features. The preservation of the layering and geographical occurrence of these four craters suggests that they could be ash layers deposited from numerous episodes from the

Tharsis Tharsis () is a vast volcanic plateau centered near the equator in the western hemisphere of Mars. The region is home to the largest volcanoes in the Solar System, including the three enormous shield volcanoes Arsia Mons, Pavonis Mons, and Asc ...

volcanoes. Voluminous volcanic episodes could have produced large volumes of layered rock that could have been rapidly buried and protected from cratering. The great detail available with HiRISE shows the layers to be both numerous and varied. Some layers are far harder than others because they form steep sides. Other layers form slopes. This same arrangement is common on the Earth. Steep slopes and slopes are easily observed in the walls of the Grand Canyon; slopes often occur when shale erodes into clay. If clay exists in some layers, then they were probably formed when water was present. Clay requires water to form. So the slopes may show periods of time when water covered the area. Perhaps life was abundant then. Click on the image below of the wall of Oudemans crater for a good view of these layers.

References

{{DEFAULTSORT:Oudemans (Crater) Impact craters on Mars Phoenicis Lacus quadrangle