provide a description of a spatial extent

[pvgenuchten]

quite common in DC, but also available as extent>gmd_EX_GeographicDescription in iso is the option to provide the spatial extent as a description (usually a term from a location glossary)

suggestion would be to allow on extent > spatial > an optional description field alongside bbox and crs

on the iso19139 serialisation the element would be serialised as

<gmd:EX_GeographicDescription>
   <gmd:geographicIdentifier>
      <gmd:MD_Identifier>
         <gmd:code></gmd:code>
      </gmd:MD_Identifier>
   </gmd:geographicIdentifier>
</gmd:EX_GeographicDescription>