The photo was taken on 14 January 2004 from 275 kilometres above the surface by the High Resolution Stereo Camera (HRSC) @ a resolution of 12 metres
per pixel, and it shows a portion of Valles Marineris: for those interested in looking at the areas indicated in the OP in their own context (which
would be the first thing to do in cases like this one, IMHO), here they are (see green rectangles).
Note: image # 1 has been rotated 180 degrees (I don't know the why).
A big version of the image (4096x4096) can be found here:
here.
berlinadmin.dlr.de...
www.esa.int...
In my opinion there's nothing worthy to be called "anomalous", they are formations perfectly consistent with the geomorphology of the rest of whole
area, and honestly, nothing suggests any artificial origin: if there's something obviously artificial there, then it has to have been buried very
well.
Thanks for sharing
