Topic:
Some markers not upgraded and others become more widespread after upgrade

Description:
After upgrading a project from IESX10.2 to GeoFrame 3.7.1 some markers are not
upgraded at all while others become more widespread. Why?

Solution:
The upgrade is in fact working correctly and the problem relates to the unusual
pattern of marker/surface associations in the IESX project. Of the 30 markers in
the project over half of them were associated with the same geophysical surface.
In GeoFrame the data model does not allow multiple formations (markers) to be
associated with the same geophysical surface (horizon). To resolve this problem
the upgrade process forces the associations  to be unique by assigning the last
upgraded formation name to the geophysical surface. This is why one of the
markers becomes more widespread because it is the last marker associated with
the surface in the upgrade process.  It also explains why a number of markers
are 'not upgraded' - in fact they are still in the project but are renamed to
the marker that became more widespread. The following simple scenario may help
to explain the process:

IESX10p2 project:

Geological Formation     Depth         Associated Geophysical Surface
Formation_a               100             Geophys_sur_a
Formation_b               200             Geophys_sur_a  (has same associated
                                          surface as Formation_a)
Formation_c               300             Geophys_sur_c


After upgrade to GF3.7.1:
Geological Formation      Depth         Associated Geophysical Surface
Formation_b                100            Formation_b (Formation_a still exists
                                          but is renamed as Formation_b)
Formation_b                200            Formation_b (renames Geophys_sur_a to
                                          Formation_b)
Formation_c                300            Formation_c (renames Geophys_sur_c to
                                          Formation_c)

RESULT: Formation_b becomes more widespread after upgrade.

The horizon surfaces in GF3.7.1 are :
formation_b         (this is actually geophys_surf_a renamed)
geophys_surf_b
formation_c         (this is geophys_surf_c renamed)


The upgrade log file records the name changes:

3 formations to process.
  Loading formation #1 of 3...
     Changing the associated horizon name "geophys_surf_a" to the formation name "form_a".
     The associated horizon "form_a" will be marked as geological.
  Loading formation #2 of 3...
     Changing the associated horizon name "form_a" to the formation name
"form_b".
     The associated horizon "form_b" will be marked as geological.
  Loading formation #3 of 3..
     Changing the associated horizon name "geophys_surf_c" to the formation name "form_c".
     The associated horizon "form_c" will be marked as geological.
3 formations loaded.


To resolve the problem either:
a) Restore the IESX 10p2 project, check the marker associations are unique then
   re-upgrade to GeoFrame.

b) Reload the markers from ASCII.





Last Modified on: 07-APR-00