This question already has an answer here:
[Update: This was not a duplicate of the other question since the mountain shape is rather different. This was already stated in my question below.]
This question is a bit similar to this other question about pyramid-shaped mountains.
In this case though the mountain is also in Antarctica but it looks as shown in below picture.
(This picture is taken at Princess Elisabeth station)
So I was curious on if this mountain in the foreground, and the one behind it, could be volcanoes? Or are there examples where non-volcano mountains form into these shapes?