Mangala Fossa is a
graben in the
Memnonia quadrangle
The Memnonia quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Memnonia quadrangle is also referred to as MC-16 (Mars Chart-16).
The quadrangle is ...
of
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 ...
, located near , which originated in the
Hesperian and Amazonian epochs. The graben is located at the head of the
outflow channel
Outflow channels are extremely long, wide swathes of scoured ground on Mars. They extend many hundreds of kilometers in length and are typically greater than one kilometer in width. They are thought to have been carved by huge outburst floods.
...
Mangala Valles
The Mangala Valles are a complex system of criss-crossing channels on Mars, located in the Tharsis region and in the Memnonia quadrangle. They originated in the Hesperian and Amazonian epochs. They are thought to be an outflow channel system, car ...
, which is thought to have been formed by at least two catastrophic flood events during the same geological period, leading to the release of vast quantities of water from Mangala Fossa onto the Martian surface. The flooding was probably initiated by the emplacement of a dike radiating from the volcano
Arsia Mons
Arsia Mons is the southernmost of three volcanoes (collectively known as Tharsis Montes) on the Tharsis bulge near the equator of the planet Mars. To its north is Pavonis Mons, and north of that is Ascraeus Mons. The tallest volcano in the So ...
, resulting in the formation of the graben, Mangala Fossa, at the channels' head. This dike breached a pressurized
aquifer
An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials ( gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characteris ...
trapped beneath a thick "
cryosphere
]
The cryosphere (from the Ancient Greek, Greek ''kryos'', "cold", "frost" or "ice" and ''sphaira'', "globe, ball") is an all-encompassing term for those portions of Earth's surface where water is in solid form, including sea ice, lake ice, ri ...
" (layer of frozen ground) beneath the surface. As the floor of the graben subsided, water found its way up one or both of the faults in the crust that defined the edges of the graben and spilled into the depression, eventually filling it and overflowing at the lowest point on the rim to erode the Mangala Valles channels.
[Hanna, J. and R. Phillips. 2005. Tectonic pressurization of aquifers in the formation of Mangala and Athabasca Valles on Mars. LPSC XXXVI. Abstract 2261.]
"
Mangala
Mangala (Sanskrit: मङ्गल, IAST: ) is the personification, as well as the name for the planet Mars, in Hindu literature. Also known as Lohita (), he is the celibate deity of anger, aggression, as well as war. According to Vaishnavism, ...
" is the name for
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 ...
in
Jyotish (or Hindu) astrology.
Gallery
Image:Mangala Valles based on day THEMIS.png, Mangala Fossa and Mangala Valles
(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 ...
)
Image:Graben in Memnonia Fossae.JPG, Graben in Memnonia Fossae – possible result of magmatic dikes, rather than regional tectonic stretching 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 ...
Image:Close up view to beginning of Mangala Valles based on day THEMIS.png, Mangala Valles - head region
(THEMIS)
See also
*
Outburst flood
In geomorphology, an outburst flood—a type of megaflood—is a high-magnitude, low-frequency catastrophic flood involving the sudden release of a large quantity of water. During the last deglaciation, numerous glacial lake outburst floods were ca ...
*
Outflow channels
Outflow channels are extremely long, wide swathes of scoured ground on Mars. They extend many hundreds of kilometers in length and are typically greater than one kilometer in width. They are thought to have been carved by huge outburst floods.
...
Further reading
* Leask, H. J., L. Wilson, and K. L. Mitchell (2006)
Formation of Ravi Vallis outflow channel, Mars: Morphological development, water discharge, and duration estimates J. Geophys. Res., 111, E08070, doi:10.1029/2005JE002550.
* Wilson, L.; Head, J.W.; Leask, H.J.; Ghatan, G.; Mitchell, K.L. (2004)
Factors Controlling Water Volumes and Release Rates in Martian Outflow Channels Lunar and Planetary Science XXXV (2004).
References
External links
Lunar and Planetary Institute
{{Portal bar, Solar System
Valleys and canyons on Mars
Memnonia quadrangle