Nature magazine published on October 3the results of image analysis of the Martian surface taken by various spacecraft ( Mars Global Surveyor , Mars Odyssey , Mars Reconnaissance Orbiter
and Mars Express).
Eden patera ... the
footprint of a super- volcano
in red, areas of relatively high land, in blue and gray, the lower areas - / image JPL NASA / GSFC / Arizona State University
Eden Patera - the dark color indicates the presence of young materials - Photo: ESA / Mars Express / Freie University - Natural History Museum.
The geologist Joseph Michalski (Institute of Earth Sciences Tucson, USA ) and the volcanologist Jacob Bleacher (NASA Goddard Space Flight Center, USA ) submit a new
hypothesis about the craters on the surface of the Red Planet, regarded up to now as
impact craters ... but that could be the remains of ancient "super- volcano " active there are four billion years.
This hypothesis is linked with studies of NASA , based on measurements made by Curiosity ( 07.2013 journal Science ) that indicate a major change occurred on Mars at that time , who probably
originated from volcanic eruptions of exceptional magnitude .
Eden
patera - Photo undated by the NASA, on the possible location of a Martian super- volcano - it reports a relief " not compatible " with the assumption of a crater impact - Photo NASA / JPL / MSSS / Google
Among the craters dotting the surface of Arabia Terra , an area north of Mars , Eden patera has a depression 55 km wide, 85 km long, with a depth of 1800
meters, looking terrestrial collapse calderas consecutive to super- eruption ( Yellowstone or Toba type).
The scientists describe
three separate calderas in the depression, with possible traces of solidified lava lake and a volcanic vent .
These
volcanoes differ from other Martian volcanoes , like the famous Olympus Mons, one of the largest volcanoes in the solar system, which has issued the lava for billions of years.
The super- volcanoes of Arabia Terra could have expelled with extreme violence enough dust to cover in March of rubble in the first billion years of the Martian history. They would have been able
to release huge amounts of gas , alter the climate and play an important
role in the early evolution of the planet and its habitability.
Other structures
are candidates for the title of super- volcano : Euphrates patera and Siloe patera, respectively deep of 700 meters and 1750 meters. These volcanoes have produced
powdery deposits identified by the NASA rovers on both landing Gale Crater and Meridiani Planum sites.
A hypothesis already " challenged " by other scientists :
This interesting theory , which sticks to certain geological features of Mars and has analogies with terrestrial volcanic structures, is based only on qualitative decriptions .
It must be corroborated by other evidence ... or thrown into oblivion .
The future will tell !
Sources :
- Nature - Supervolcanoes within an ancient volcanic province in arabia Terra, Mars - by J.R. Michalski & J.E.Bleacher - link
Magazine Nature cover : Blast from the past - Enigmatic craters are evidence of ancien Martian supervolcanoes.
- Nat Geo - Supervolcanoes rocked early Mars / Big calderas point to early magma outbursts that shapped the red planet.
