Melas Chasma is a canyon 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 ...

, the widest segment 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 ...

canyon system,HiRISE , Eroding Layers in Melas Chasma (PSP_004054_1675)
/ref> located east of Ius Chasma at 9.8°S, 283.6°E in Coprates quadrangle. It cuts through layered deposits that are thought to be

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sa ...

s from an old

lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...

that resulted from runoff of the valley networks to the west. Other theories include windblown sediment deposits and volcanic ash. Support for abundant, past

water Water (chemical formula ) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living ...

in Melas Chasma is the discovery by MRO of hydrated sulfates. In addition, sulfate and iron oxides were found by the same satellite. Although not chosen as one of the finalists, it was one of eight potential landing sites for the ''

Mars 2020 Mars 2020 is a Mars rover mission forming part of NASA's Mars Exploration Program that includes the rover '' Perseverance'', the small robotic, coaxial helicopter '' Ingenuity'', and associated delivery vehicles. Mars 2020 was launched from ...

'' rover, a mission with a focus on astrobiology. The floor of Melas Chasma is about 70% younger massive material that is thought to be volcanic ash whipped up by the wind into eolian features. It also contains rough floor material from the erosion of the canyon walls. Around the edges of Melas is also much slide material.Witbeck, Tanaka and Scott, Geologic Map of the Valles Marineris Region, Mars; USGS I-2010; 1991. In a recent study of southwestern Melas Chasma using high-resolution image, topographic and spectral datasets eleven fan-shaped landforms were found. These fans add to growing evidence that Melas Chasma once held a lake that had fluctuating levels. Using HiRISE images, CTX images, and DEM's, a team of researchers mapped many channels and inverted channels in Melas Chasma. A

digital elevation model A digital elevation model (DEM) or digital surface model (DSM) is a 3D computer graphics representation of elevation data to represent terrain or overlaying objects, commonly of a planet, moon, or asteroid. A "global DEM" refers to a discrete g ...

(DEM) is a digital model or 3D representation of a terrain's surface. In addition, they found dendritic networks of channels in the plateaus just above the Chasma. Channels appeared to have formed at different times, hence there were "wet-dry" phases in the history of Melas Chasma. The whole region may have had liquid water for extended periods in the early

Hesperian The Hesperian is a geologic system and time period on the planet Mars characterized by widespread volcanic activity and catastrophic flooding that carved immense outflow channels across the surface. The Hesperian is an intermediate and transitio ...

.Davis, J., et al. 2017. FLUVIAL MAPPING AND STRATIGRAPHY OF THE SOUTH-WESTERN MELAS BASIN AND PLATEAU, VALLES MARINERIS, MARS: EPISODIC FLUVIAL PHASES AND IMPLICATIONS FOR CLIMATE. Lunar and Planetary Science XLVIII (2017). 1991.pdf Image:Marsplateau odyssey big.gif, Combined infrared and daytime observation of Melas Chasma. The shadowed regions (blue) indicate successive landslides. Image:Melas Chasma.JPG, Cliff in Melas Chasma, as seen by

THEMIS In Greek mythology and religion, Themis (; grc, Θέμις, Themis, justice, law, custom) is one of the twelve Titan children of Gaia and Uranus, and the second wife of Zeus. She is the goddess and personification of justice, divine order, fai ...

. Click on image to see relationship of Melas to other features. Image:Melas Chasma Layered Deposits.JPG, Two views of Melas Chasma Layered Deposits, as seen by

HiRISE High Resolution Imaging Science Experiment is a camera on board the '' Mars Reconnaissance Orbiter'' which has been orbiting and studying Mars since 2006. The 65 kg (143 lb), US$40 million instrument was built under the direction ...

. Left picture lies north of other picture on the right. Pictures are not the same scale. Click on image to see details of layers. Image:Layers in Monument Valley.jpg, Layers in Monument Valley. These are accepted as being formed, at least in part, by water deposition. Since Mars contains similar layers, water remains as a major cause of layering on Mars.

References

External links

*

Lakes on Mars - Nathalie Cabrol (SETI Talks) * {{Portal bar, Solar System Valleys and canyons on Mars Coprates quadrangle Mars 2020

See also

References

External links