Topic:
Guidelines for using GeoFrame Projection Systems with IESX.

Description:
When sharing seismic you will receive a warning message stating that the datums
do not match. Below is a guide to help you make the right decision on what to do
next.

This will not be an issue in GeoFrame 4.0.       

Solution:
I. Introduction

During GeoFrame project creation the user is asked to define a storage
coordinate system and a display coordinate system.  Each is composed of
a projection system and a geodetic system.  The storage coordinate system
defines the projection and geodetic system which will be used for data
stored in GeoFrame.  The display coordinate system defines the projection
and geodetic system which will used to view stored data for applications
such as IESX.


II. Guidelines

There are a few guidelines which should be followed when defining and
using the coordinate systems in a project to preserve data
integrity.  The guidelines are as follows:

  1. The project storage coordinate system should not be changed once
  its geodetic and projection systems have been defined and any data has
  been loaded to the project.

  2. The project display coordinate system should be used to view the
  data in whatever projection system the user desires.  The geodetic system
  of the display coordinate system must match that of the storage coordinate
  system.

  3. When IESX shares data from different projects the storage
  coordinate systems geodetic datum should match or be equivalent.  This
  insures that the data will display and tie correctly where appropriate.
  A message from IESX will inform the user if the projects have differing
  geodetic datum or projections systems.

  4. It is recommended that all projects for a region use the same
  geodetic datum for their storage coordinate system setting.  This
  allows easy sharing data by IESX.

  5. In GeoFrame 3.7 and later releases IESX data loaders support loading
  and conversion of data with geodetic datum different from that of the
  storage coordinate system.

 



Last Modified on: 26-MAY-00