A TIN volume surface is a composite of points in a base surface and comparison surface.
A TIN volume surface provides an exact difference between the base and comparison surfaces. Therefore, the Z-value of any point in the volume surface is precisely the difference between the Z of the comparison surface at that point and the base surface at that point. This is true whether the comparison and base surfaces are both grid surface, both TIN surfaces, or one of each.
A volume surface is a persistent surface object. Therefore, you can display cut and fill contours, cut and fill points, and add labels to it. You can view volume properties (cut, fill, net) of a volume surface by selecting Surface Properties. For more information, see To Edit and View the Surface Definition.