Vertical Reference System

A vertical reference system is a 3D coordinate reference system in which position is defined by latitude, longitude, height or depth and a linear unit of measure, for example, feet or metres.

When the Z values in a vertical reference system represent depths, the Z axis direction is “positive-down”. (This is consistent with the HIPS and SIPS depth convention.)

In HIPS and SIPS the identification of the vertical reference system information used for a project can be added to a surface during its creation. Alternatively, it can be added to the Vertical Coordinate System field in the Properties of an existing surface.

A database of defined vertical reference systems is available in HIPS and SIPS through the Vertical System Editor. This information is drawn from the European Petroleum Survey Group (EPSG) database of reference systems, which can be found at: http://www.epsg-registry.org.¹

Procedure

To open the Vertical Reference System Editor:

1. Select the Reference System Editor command.

¹ Use of material from OGP Surveying and Positioning Committee’s EPSG Geodetic Parameter Registry does not imply endorsement by OGP Surveying and Positioning Committee of CARIS products or services.