There are a few points to remember when looking at any image like this, in this case from the Sol 4073 camera: We can see LOTS of things in the Martian soil and background that resemble things we know. Our brains that does. We liken certain shapes to other things we are familiar with.
That being said..
This sure as hell looks like a dome.
The picture in total here:
The location to focus on: The top right. On that mountain. You know, right where the dome is?
OF course if the Jet Propulsion Laboratory linked this on their own site, you'd certainly think less of a conspiracy they are trying to hide of life on the planet and more simply of a rock formation that we have taken and created a name for.
But again..
It just looks like a dome. And near it a path? Or a structure that seems to compliment the dome? Perhaps a guard shack?
However, the tricks your eyes can do are amazing.
After all, it's not just a dome I see in this picture.
Note the middle of the image, towards the left. There is a rock that looks uniquely like the online fad the Annoying Orange. To better help, a visual presentation of that:
While I certainly don't think the annoying orange formation is anything more than a rock with shadows that resemble a mouth and eyes, I will say this: That dome? Yes indeed. That looks a lot like a dome.