Maybe it is a liquid.
Notice the shape of the edge in some areas. If that was a hole, would those outcroppings be able to support themselves without collapsing? Mars' gravity is a lot less than on Earth, so who knows.
Space/Science » in reply to As you pointed out in another post...
Notice the shape of the edge in some areas. If that was a hole, would those outcroppings be able to support themselves without collapsing? Mars' gravity is a lot less than on Earth, so who knows.