Let us assume the sphere is touching the plane of the "floor" in the point А which is at x, y= 0,0
Screenshot - http://sitesman.com/s/1008-Photoshop_2016-07-25_17-04-20.png
We move the point A for example along the x axis 5 meters to one side. And what is on the right drawing should happen. The lower semisphere should be deformed, the upper should stay as it is.