Eridania Lake is a theorized ancient lake on

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...

with a surface area of roughly 1.1 million square kilometers. It is located at the source of the Ma'adim Vallis outflow channel and extends into

Eridania quadrangle The Eridania quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program. The Eridania quadrangle is also referred to as MC-29 (Mars Chart-29). The Eridania quadr ...

and the Phaethontis quadrangle. As Eridania Lake dried out in the late

Noachian epoch The Noachian is a geologic system and early time period on the planet Mars characterized by high rates of meteorite and asteroid impacts and the possible presence of abundant surface water. The absolute age of the Noachian period is uncertai ...

it divided into a series of smaller lakes. PIA22059 fig1eridaniadepths.jpg, Map showing estimated water depth in different parts of Eridania Sea This map is about 850 km (530 miles) across. PIA22059 fig1eridaniadepthslabeled.jpg, Features around Eridania Sea labeled Later research with

CRISM The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is a visible-infrared spectrometer aboard the Mars Reconnaissance Orbiter searching for mineralogic indications of past and present water on Mars. The CRISM instrument team compris ...

found thick deposits, greater than 400 meters thick, that contained the minerals

saponite Saponite is a trioctahedral mineral of the smectite group. Its chemical formula is . It is soluble in sulfuric acid. It was first described in 1840 by Svanberg. Varieties of saponite are griffithite, bowlingite and sobotkite. It is soft, m ...

, talc-saponite, Fe-rich

mica Micas ( ) are a group of silicate minerals whose outstanding physical characteristic is that individual mica crystals can easily be split into extremely thin elastic plates. This characteristic is described as perfect basal cleavage. Mica is ...

(for example, glauconite- nontronite), Fe- and Mg-serpentine, Mg-Fe-Ca-

carbonate A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...

and probable Fe-

sulphide Sulfide (British English also sulphide) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to chemical compounds la ...

. The Fe-sulphide probably formed in deep water from water heated by

volcano A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are ...

es. Such a process, classified as hydrothermal may have been a place where

life Life is a quality that distinguishes matter that has biological processes, such as signaling and self-sustaining processes, from that which does not, and is defined by the capacity for growth, reaction to stimuli, metabolism, energ ...

began. PIA22058 hireseridanaregion.jpg, Deep-basin deposits from the floor of Eridania Sea. The mesas on the floor are there because they were protected against intense erosion by deep water/ice cover.

measurements show minerals may be from seafloor hydrothermal deposits. Life may have originated in this sea. PIA22060 hireseridania.jpg, Diagram showing how volcanic activity may have caused deposition of minerals on floor of Eridania Sea. Chlorides were deposited along the shoreline by evaporation.

References

External links

Lakes on Mars – Nathalie Cabrol (SETI Talks)
Surface features of Mars Former lakes {{Mars-stub

See also

References

External links