'probably' means 'could be'.' whats your problem? We are all working towards the same end, so I have to assume that you are just a bit grumpy today and got out of bed the wrong side this morning.
"Could be" not "it is". You are talking about Mars, another planet, bigger than the moon that is hanging above our heads. You should go out and have a look. See this gigantic sphere ? Mars is much more bigger and much more fare away. We have so less information about the moon and it is that near in relation.
HiRISE at this point has shot images of 1 % of the Mars surface in some sort of higher resolution and you are talking about details in the scale of a few inches, taken in one moment under a certain angle of light in a tiny area without exact criterion to definite the size scale and without the sharpness necessary to recognize its exact shapes. There is no way to say "it is", only a "looks like ", which is speculation by blind men in a dark room at night. And they are chained to their chairs.
For those who do not like playing with dots, who would like to get a feeling of the real picture, some old, old news from a german newspaper dated 6th of march 1998 entitled: "NASA discovers ice on the moon." "...The NASA sonde LUNAR PROSPECTOR orbiting the moon in a close orbit has discovered several areas where there is ice under the rocklayers, first signs, that there is water on the surface of the moon, said project member William Feldman in Washington yesterday. The ice occurences have been detected in a some thousand square miles area in the polar regions. The datas came in in february 1998. The volume of the detected ice is estimated of about between 11 to 330 million tons, Feldman said....."
11 to 330 million tons ( metric tons) of water ice on the surface of the moon detected and announced by NASA in 1998. Now we have the year 2010. In 2009, 11 years after 1998 NASA and its little helpers have announced exactly the same discovery to the public , whilst bombarding the capheus crater in the search for the same water ice, they have found 11 years before. They are fooling us without consequences and there must be a lot of people working inside of NASA that do not like that either. I do not want to talk about or comment on dots anymore, but will do , if necessary.
Yes, I think it probably is. There are a few things in this picture that could be not naturally occurring rocks, as well as the earthworks in the distance. There may be other pictures of it if you search under the site code.
This is an interesting "rock ". The ogee shape is often used in many wood working projects (trim and counter-top edging). As you see in the examples, corbels or brackets can be quite ornate. http://marsrovers.jpl.nasa.gov/gallery/all/1/p/2174/1P321270621EFFABPRP2388L2M1.JPG
". The ogee shape is often used in many wood working projects (trim and counter-top edging). As you see in the examples, corbels or brackets can be quite ornate. 
