Mangala Fossa

{{Short description|Geological depression on Mars}} {{use dmy dates|date=December 2015}} {{Infobox feature on celestial object |name = Mangala Fossa |image = [[File:Mangala Valles based on day THEMIS.png|250px]] |caption = Mangala Fossa and Mangala Valles<br />([[Thermal Emission Imaging System|THEMIS]] image) |coordinates = {{coord|11.6|S|151.0|W|globe:mars_type:landmark|display=inline,title}} |length = 828.0 km }}

'''Mangala Fossa''' is a [[graben]] in the [[Memnonia quadrangle]] of [[Mars]], located near {{coord|11.6|S|151.0|W|globe:mars}}, which originated in the [[Martian geologic timescale|Hesperian and Amazonian epochs]]. The graben is located at the head of the [[outflow channel]] [[Mangala Valles]], 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]], resulting in the formation of the graben, Mangala Fossa, at the channels' head. This dike breached a pressurized [[aquifer]] trapped beneath a thick "[[cryosphere]]" (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.<ref>{{cite web|url=https://www.msss.com/http/ps/channels/channels.html|title=Mars Channels and Valleys|publisher=Msss.com|access-date=13 January 2015}}</ref><ref name="Carr2006">{{cite book|author=Michael H. Carr|title=The surface of Mars|url=https://books.google.com/books?id=uLHlJ6sjohwC|access-date=21 March 2011|date=2006|publisher=[[Cambridge University Press]]|isbn=978-0-521-87201-0}}</ref><ref>Carr, M. 1979. Formation of martian flood features by release of water from confined aquifers. Journal of Geophysical Research 84: 2995-3007.</ref><ref>Hanna, J. and R. Phillips. 2005. Tectonic pressurization of aquifers in the formation of Mangala and Athabasca Valles on Mars. LPSC XXXVI. Abstract 2261.</ref><ref name="LPS-2004">{{cite web |last1=Ghatan |first1=Gil J. |last2=Head |first2=James W. |last3=Wilson |first3=L. |last4=Leask |first4=H.J. |title=Mangala Valles, Mars: Investigations of the Source of Flood Water and Early Stages of Flooding - Lunar and Planetary Science XXXV (2004) |url=https://www.lpi.usra.edu/meetings/lpsc2004/pdf/1147.pdf |date=2004 |work=[[Lunar and Planetary Institute]] |access-date=6 December 2015 }}</ref><ref name="JGR-20070224">{{cite journal |last1=Leask |first1=Harald J. |last2=Wilson |first2=Lionel |last3=Mitchell |first3=Karl L.|title=Formation of Mangala Fossa, the source of the Mangala Valles, Mars: Morphological development as a result of volcano-cryosphere interactions |date=24 February 2007 |journal=[[Journal of Geophysical Research]] |volume=112 |issue=E02011 |pages= E02011|doi=10.1029/2005JE002644 |bibcode=2007JGRE..112.2011L |url=https://eprints.lancs.ac.uk/31116/1/2005JE002644.pdf |doi-access=free }}</ref><ref name="JGR-20070804">{{cite journal |last1=Leask |first1=Harald J. |last2=Wilson |first2=Lionel |last3=Mitchell |first3=Karl L.|title=Formation of Mangala Valles outflow channel, Mars: Morphological development and water discharge and duration estimates |date=4 August 2007 |journal=[[Journal of Geophysical Research]] |volume=112 |issue=E08003 |pages= E08003|doi=10.1029/2006JE002851 |bibcode=2007JGRE..112.8003L |url=https://eprints.lancs.ac.uk/id/eprint/31123/1/2006JE002851.pdf |doi-access=free }}</ref>

"[[Mangala]]" is the name for [[Mars]] in [[Hindu astrology|Jyotish (or Hindu) astrology]].

==Gallery== {{multiple image |caption_align=center |header=Mangala Fossa and Mangala Valles ([[USGS]] maps) |align=center |width= |direction=horizontal |image1=USGS-Mars-MC-16-MemnoniaRegion-mola.png |caption1=Context |width1=400 |image2=USGS-Mars-MC-16-MemnoniaRegion-mola-crop.png |caption2=Close-up |width2=133 |footer_align = center |footer=[[Topographic map]]s ([[Mars Orbiter Laser Altimeter|MOLA]]) – [[Memnonia quadrangle|Memnonia region]] of [[Mars]] (left), and a close-up (right) of the location of Mangala Fossa and the source of the [[Mangala Valles]] [[outflow channel]] }} <gallery align="center"> Image:Mangala Valles based on day THEMIS.png|Mangala Fossa and Mangala Valles<br />([[Thermal Emission Imaging System|THEMIS]]) Image:Graben in Memnonia Fossae.JPG|Graben in Memnonia Fossae – possible result of magmatic dikes, rather than regional tectonic stretching as seen by [[HiRISE]] Image:Close up view to beginning of Mangala Valles based on day THEMIS.png|Mangala Valles - head region<br />(THEMIS) </gallery>

==See also== {{commons category|Mangala Fossa}} * [[Outburst flood]] * [[Outflow channels]]

==Further reading== * Leask, H. J., L. Wilson, and K. L. Mitchell (2006), [http://onlinelibrary.wiley.com/doi/10.1029/2005JE002550/pdf 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), [https://www.lpi.usra.edu/meetings/lpsc2004/pdf/1151.pdf Factors Controlling Water Volumes and Release Rates in Martian Outflow Channels], [[Lunar and Planetary Science]] XXXV (2004).

==References== {{Reflist|30em}}

==External links== * [https://www.lpi.usra.edu Lunar and Planetary Institute]

[[Category:Valleys and canyons on Mars]] [[Category:Memnonia quadrangle]]