This image, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, show pits and tectonic 'grabens' in the Phlegethon Catena region of Mars.

The HRSC obtained this images during orbit 1217 with a ground resolution of approximately 11.9 metres per pixel. The scenes show the region of Phlegethon Catena, centred at approximately 33.9 degree South and 253.1 degree East.

Located south-east of the Alba Patera volcano, Phlegethon Catena is a region exhibiting a high density of tectonic grabens, which are blocks of terrain that have dropped relative to their surroundings as a result of a geological extension of the crust.

It is unclear what process is responsible for the chain of depressions.

One possibility is the collapse of the surface due to the removal of subsurface materials, while other suggestions include that tension cracks may have formed in the subsurface and caused subsequent collapse.

The colour scenes have been derived from the three HRSC-colour channels and the nadir channel. The perspective views have been calculated from the digital terrain model derived from the stereo channels.

The 3D anaglyph image was calculated from the nadir and one stereo channel. Image resolution has been decreased for use on the internet.



Source: ESA

Posted by: Edwin    Source