This photo shows other interesting features. On the next [age for reference is the original raw photo, destreaked and contrast stretched. Note the many straight edges. 'a" appears to be a doorway into the dark rock. "b" shows box like and straight edges, as if they were boxes at a theater. At "c" there are hundreds of perfectly straight ridges and gullies, perhaps artificial. Below "d" I have superimposed a circle to show the edge of the mesa is close to part of a circle in shape. To the left of "e" there are two circles, each of which follows the shape of the mesa. Below "e" there are many more straight grooves. There are also two 90 degree angled features marked.
Note the doorway shaped formation: