GEX 1.0 is an XML Schema implementation derived from ISO 19115-1, Geographic Information - Metadata - Part 1: Fundamentals, Clause 6.6.1. It includes elements for specifying geospatial properties of a resource, including extent and spatial reference systems. The XML schema was encoded using the rules described in ISO/TS 19139:2007, Clause 8 and implementation approach from ISO/TS19115-3, Clause 8.

The namespace URI for gex 1.0 is http://standards.iso.org/iso/19115/-3/gex/1.0.

gex.xsd is the XML Schema document to be referenced by XML documents containing XML elements in the gex 1.0 namespace or by XML Schema documents importing the gex 1.0 namespace. This XML schema includes (indirectly) all the implemented concepts of the gex namespace, but it does not contain the declaration of any types.

extent.xsd implements the UML conceptual schema defined in ISO 19115-1, Geographic Information - Metadata - Part 1: Fundamentals, Clause 6.6.1. It was created using the encoding rules defined in ISO 19118, ISO 19139, and the implementation approach described in ISO 19115-3 and contains the following classes (codeLists are bold): EX_BoundingPolygon, EX_Extent, EX_GeographicBoundingBox, EX_GeographicDescription, AbstractEX_GeographicExtent, EX_SpatialTemporalExtent, EX_TemporalExtent, and EX_VerticalExtent

The gex 1.0 namespace imports these other namespaces:

Schematron rules for validating instance documents of the gex 1.0 namespace are in gex.sch. Other schematron rule sets that are required for a complete validation are: gco.sch, gmw.sch, mcc.sch, and mcc.sch

When revisions to these schema become necessary, they will be managed in the ISO TC211 Git Repository.