Point cloud delamination happens only when visiting the same area, but loop closure is not triggered. This occurs only when scan lines do not intersect or have low percentage of overlap.
Generated point cloud will be delaminated, there is visible differentiation between point cloud that is generated. Easiest to recognize delamination is by changing to 2D view and inspecting generated point cloud from the top to see if there is a distinct vertical separation in generated point cloud.
To avoid or minimize delamination, recommendation is to follow Operating recommendations in Quick start guide.