f Integration of 3D subsurface models of different scales

The integration of 3D subsurface rnodels derived from geophysical, petrophysical and geological data on computers bas always been a problem in Exploration and Production of Oil and Gas. Especially the discrepancy between the various geometrical scales used for the various geophysical and geological properties has prohibited the availability of a fully integrated computerized facility to build, rnanipulate and view the 3D subsurface model geometry with their properties at all scales. An extension has been constructed to the GOCAD interactive 3D modelling facility to handle models at different scales describing different properties in an integrated way.