Metadata File Formats
(see Metadata Attributes in Section 4.2.4) supplied as per Excel template or alternatively in file formats suitable for reading and loading.
ASCII
CSV (Comma separated values)
Text (Tab delimited values)
MS Excel
Excel 2003 (.xls)
Excel 2007 – Excel 365 (.xlsx)
Metadata Catalogues
Most large organisations that distribute spatial data, catalogue the existence of that data using a metadata catalogue system such as GeoNetwork opensource (geonetwork-opensource.org). AusSeabed Contributing Hubs must provide a catalogue that can be harvested by AODN (and others). The preferred mechanism employed is an Open Geospatial Consortium (OGC) compliant Catalogue Service for the Web (CSW). AusSeabed requires that metadata entries be systematised to support downstream searching and filtering.
There are several metadata standards for describing spatial data. However, ISO19115 standard continues to grow in popularity. The standard itself provides a wide range of flexibility in the form of XML format. It is rarely possible for a system to understand the semantics of every component of XML that meets the standard. Likewise, the standard permits different ways of representing the same information. What have emerged are profiles of the ISO19115 that have agreed meaning among subsets of the spatial community.
Relevant attributes captured, will be stored in an ISO-19115-3 compliant repository.
In GA’s case this will be eCat (ecat.ga.gov.au) which is shared with other external catalogues such as the Australian Ocean Data Network (https://catalogue.aodn.org.au/geonetwork/srv/eng/catalog.search#/home )
All attributes captured will be stored in the AusSeabed Data Register.
Relevant metadata fields compiled from above must be able to be published using ISO19115-3 metadata through a catalogue service for the web - nominally GeoNetwork. GA uses GeoNetwork as it implements the following protocols to assist in the function of publishing and ingesting metadata:
OGC CSW (Open Geospatial Consortium – Catalogue Service for the Web)
OAI-PMH (Open Archives Initiative Protocol for Metadata Harvesting)
OpenSearch
Z39.50 (Z39.50 is an international standard client–server, application layer communications protocol for searching and retrieving information from a database over a TCP/IP computer network. It is covered by ANSI/ISO standard Z39.50, and ISO standard 23950)
an Application Programming Interface (API) to interact with other systems and a DCAT/RDF search service.
GeoNetwork provides at least three method of editing metadata: a) a simple interface; b) the full interface; and c) an XML editor. Most metadata can be entered in the simple interface; however, a number of fields (listed in the table below) require the full editing interface or XML editor (or import).
Attribute | Location in XML |
Abstract | IdentificationInfo/Abstract |
Title | IdentificationInfo/Citation/Title |
Lineage | resourceLineage |
Keywords | 1<mri:descriptiveKeywords> 2 <mri:MD_Keywords> 3 <mri:keyword> 4 <gco:CharacterString>marine</gco:CharacterString> 5 </mri:keyword> 6 <mri:type> 7 <mri:MD_KeywordTypeCode codeList="codeListLocation#MD_KeywordTypeCode" codeListValue="theme"/> 8 </mri:type> 9 </mri:MD_Keywords> 10</mri:descriptiveKeywords> |
Start Date | IdentificationInfo/Extent/TemporalExtent/TimePeriod/BeginPosition |
End Date | IdentificationInfo/Extent/TemporalExtent/TimePeriod/EndPosition |
Vessel (for surveys, not compilations) | Acquisition Information/Platform/Identifier Compilations should provide a list of all included Surveys in the Lineage field |
Instrument (for surveys, not compilations) | Acquisition Information/Platform/Instrument/Identifier Compilation Instruments can be determined via the metadata for each Survey included in the product. |
Vessel and instrument should also link to a valid vocabulary entry in a vocabulary server. e.g.
1<mcc:code> 2<gcx:Anchor xlink:href="'http://vocab.nerc.ac.uk/collection/C17/current/09SS' ">Southern Surveyor</gcx:Anchor> 3</mcc:code> |
Likewise, start and end ports should link to a valid vocabulary entry.
e.g. SeaDataNet Ports:
'http://vocab.nerc.ac.uk/collection/C38/current/BSH244/'
If as a Contributing Hub you have employed alternate technologies as long as the metadata can be harvested via an API like OGC CSW.
A fully marked up ISO-19115 XML example can be found here.
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