Use the Split Surface feature to split a region of a surface away from the original surface so you can work on the split region separately from the rest of the surface. The surface you split can be solid geometry or a quilt.

To create a Split Surface feature, you select contours of a single surface. The selected contours are split away from the original surface, and an identical copy of these contours is created to form the Split Surface feature. After the split, there are two surfaces: the original surface containing the contours that were not selected, and the Split Surface feature containing a copy of the selected contours.