The anomalous nature of this image has been done less justice through what seemed like the logical processing to use, rendering the strange areas indicated with color much less intriguing to behold.
The object circled near the bottom in form and shadow resembles a three or four sided pyramid, and may be one or a closely related structure (as always, the strange nature of certain extraterrestrial features only makes clear that they are something that doesn't seem to belong, though not always exactly what they are.
This is one of those cases where referring to original data, and if possible working with it yourself if you are curious, is especially recommended.