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Geosoft created metadata will conform to ISO 19139 (https://www.iso.org/standard/32557.html) or FGDC (https://www.fgdc.gov/metadata). ISO 19139 is the Geosoft default. Organizations that work under the FGDC standard will have a custom metadata editor and controls that ensure FGDC compliance. Geosoft maintains Geosoft specific metadata in a node tagged "geosoft" that will be present inside the "<gmd:MD_Metadata>" tag for ISO metadata and inside the "<metadata>" tag for FGDC metadata.
Refer to http://www.geosoft.com/schema/geo, which describes schema tags in more detail.
See also https://github.com/GeosoftInc/gxpy/blob/master/reference/SingleDataset.metadataeditor_config, which provides a comprehensive list of permissible entries for various settings.
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