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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

A professor at the UCLA / Earth and space science has discovered a geological phenomenon on the planet Mars, involving the movement of large crustal plates beneath the surface of the planet.

According to An Yin, "Mars is at a primitive stage of plate tectonics. This gives us a glimpse of the original appearance of the Earth, and can help us understand how began plate tectonics on Earth ."

It is based on the analysis of hundreds of satellite images taken by Themis - Thermal Emission Imaging System - on board the Mars Odyssey spacecraft , and high resolution camera March Orbiter .
In comparison with research in the Himalayas , Tibet, where two major tectonic plates meet, and in California, it seems that the images reveal the presence of the same faults system.

molaglobes - topographie divergente - Nasa MOLA science tea
Mars - two globes seen by the MOLA Science Team teams / Nasa showing a totally different topography. Valles Marineris
, Tharsis Montes and Olympus Mons are visible on the globe of the left, from right to left . - Image MOLA Science Team / NASA .
MArs - MOLA science team
Mars - MOLA science team - global topographic map (Mercator projection) of March - Mars Orbiter Laser Altimeter picture ( MOLA )

Mars has the longest and deepest canyon system in the solar system known as Valles Marineris ( named after the Mariner 9 probe that allowed its discovery in 71-72 ) . It is long of nearly 4,000 km, nine times that of the Grand Canyon in the USA.

Mars Plate Tectonics- Valles Marineris - Google Mars MOLA s
Mars - View of the central segment of Valles Marineris - a former circular basin, created by an impact, is cut 150 km. by a fault moving  - white dotted line the main fault separating the northern and southern blocks. - Image from Google in March created by MOLA Science Team

What phenomenon could produce this giant fracture on Mars?

Mars Plate Tectonics - Valles Marineris - Mars ReconnaissanThis scientist saw a canyon wall with a flat side , which can becreated by a fault, and even a steep cliff, comparable to the cliffs of Death Valley in California, also generated by a fault .

March - Valles Marineris - within the Rift: curved white lines in the center of the valley are layers of sediments disturbed due to the deformation induced by the displacement of the near fault - photo HRContext camera on board the Mars Reconnaissance Orbiter / Nasa

He interprets the canyon Valles Marineris as a plate boundary , with a horizontal displacement ... similar to the fault system of the Dead Sea . The two plates, assumed for the moment, have been named Valles Marineris north and south.

This hypothesis does not , however, reflects the reason that made these plates move over such a distance, or their speed, much lower than on Earth.

One hypothesis to follow and that requires confirmation .



Sources :

- UCLA - UCLA scientist discovers plate tectonics on Mars - link

- Nasa - MOLA science team - link



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