Gorgonum Chaos is a set of canyons in the
Phaethontis quadrangle
The Phaethontis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Phaethontis quadrangle is also referred to as MC-24 (Mars Chart-24).
The name com ...
of Mars. It is located at
37.5° south latitude and 170.9° west longitude. Its name comes from an
albedo feature at 24S, 154W. Some of the first gullies on Mars were found in Gorgonum Chaos. It is generally believed that it once contained a lake. Other nearby features are
Sirenum Fossae, Maadim Vallis, Ariadnes Colles, and
Atlantis Chaos. Some of the surfaces in the region are formed from the
Electris deposits.
Mapmariner.jpg, Map showing relative positions of Gorgonum Chaos, Atlantis Chaos, Magelhaens Crater and Simois Colles
Gullies
Gullies on Mars may be due to recent flowing water. Many are present in the Gorgonum Chaos.
Gullies occur on steep slopes, especially craters. Gullies are believed to be relatively young because they have few, if any craters, and they lie on top of sand dunes which are young. Usually, each gully has an alcove, channel, and apron. Although many ideas have been put forward to explain them, the most popular involve liquid water either coming from an
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 ...
or left over from old
glaciers.
There is evidence for both theories. Most of the gully alcove heads occur at the same level, just as one would expect of an aquifer. Various measurements and calculations show that liquid water could exist in an aquifer at the usual depths where the gullies begin. One variation of this model is that rising hot magma could have melted ice in the ground and caused water to flow in aquifers. Aquifers are layer that allow water to flow. They may consist of porus sandstone. This layer would be perched on top of another layer that prevents water from going down (in geological terms it would be called impermeable). The only direction the trapped water can flow is horizontally. The water could then flow out onto the surface when it reaches a break, like a crater wall. Aquifers are quite common on Earth. A good example is "Weeping Rock" in Zion National Park Utah.
![MarsTopoMap-PIA02031 modest](https://upload.wikimedia.org/wikipedia/commons/f/f3/MarsTopoMap-PIA02031_modest.jpg)
On the other hand, much of the surface of Mars is covered by a thick smooth mantle that is thought to be a mixture of ice and dust. This ice-rich mantle, a few yards thick, smooths the land, but in places it has a bumpy texture, resembling the surface of a basketball. Under certain conditions the ice could melt and flow down the slopes to create gullies. Because there are few craters on this mantle, the mantle is relatively young. An excellent view of this mantle is shown below in the picture of the Ptolemaeus Crater Rim, as seen by HiRISE.
Changes in Mars's orbit and tilt cause significant changes in the distribution of water ice from polar regions down to latitudes equivalent to Texas. During certain climate periods water vapor leaves polar ice and enters the atmosphere. The water comes back to ground at lower latitudes as deposits of frost or snow mixed generously with dust. The atmosphere of Mars contains a great deal of fine dust particles. Water vapor will condense on the particles, then fall down to the ground due to the additional weight of the water coating. When ice at the top of the mantling layer goes back into the atmosphere, it leaves behind dust, which insulating the remaining ice.
[MLA NASA/Jet Propulsion Laboratory (2003, December 18). Mars May Be Emerging From An Ice Age. ScienceDaily. Retrieved February 19, 2009, from https://www.sciencedaily.com/releases/2003/12/031218075443.htmAds by GoogleAdvertise]
See also
*
Chaos terrain
*
Electris deposits
*
Fossa (geology)
In planetary nomenclature, a fossa (pl. fossae ) is a long, narrow depression (trough) on the surface of an extraterrestrial body, such as a planet or moon. The term, which means "ditch" or "trench" in Latin, is not a geological term as such bu ...
*
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 ...
*
Lakes on Mars
In summer 1965, the first close-up images from Mars showed a cratered desert with no signs of water. However, over the decades, as more parts of the planet were imaged with better cameras on more sophisticated satellites, Mars showed evidence o ...
*
List of areas of chaos terrain on Mars
This is a list of areas of chaos terrain officially named by the International Astronomical Union on the planet Mars. Chaos terrain (or chaotic terrain) is an astrogeological term used to denote planetary surface areas where features such as ridg ...
*
Martian chaos terrain
Chaos terrain on Mars is distinctive; nothing on Earth compares to it. Chaos terrain generally consists of irregular groups of large blocks, some tens of kilometers across and a hundred or more meters high. The tilted and flat topped blocks form ...
*
Martian Gullies
Martian gullies are small, incised networks of narrow channels and their associated downslope sediment deposits, found on the planet of Mars. They are named for their resemblance to terrestrial gullies. First discovered on images from Mars Global ...
*
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.
...
*
Phaethontis quadrangle
The Phaethontis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Phaethontis quadrangle is also referred to as MC-24 (Mars Chart-24).
The name com ...
References
External links
*High resolution videos by Seán Doran of overflights of Gorgonum Chaos, based on a NASA digital terrain model
#1(higher altitude)
#2(lower altitude); se
albumfor more
{{Portal bar, Solar System
Phaethontis quadrangle
Chaotic terrains on Mars