carving or sculpture

"Dazu stone carving" or "Dazu rock sculpture"
It's a very large Buddha sculpture (I'm not sure about this word). Someone argued since it's actually a 2-dimentions work. Only some carving work upon its surface. So it's not a sculpture.
But I think maybe sculpture is used when it is an art work? And even if there are only carving work upon its surface. Its curve of the face, the body, everything can not be only 2-dimentions, it must be 3-dimentions. So I prefer sculpture. But I don't know if this is correct.
If "Dazu carving" is not famous, and can't make sense, you can imagine it to be a "Moya sculpture", "Yungang grottoes", "Leshan Great Buddha", especially "Leshan Giant Buddha". They're similar.