How to model this:

 From:  Frenchy Pilou (PILOU) 1 Oct 2013  (2 of 11) 
6202.2 In reply to 6202.1 
Project an ellipse or a circle then Projection
Maybe some use of the ShrinkTrimmedSrf (function hidden : press TAB then write it) for deform only one piece of the surface ?

Ps Possibility of a circular selection of points will be fine in this case :)

EDITED: 1 Oct 2013 by PILOU