Metadata and documentation
In order for data to remain discoverable and useable, it is important that as much information as possible is recorded about the collection methods and content of the data (at project, survey/dataset and file level) and stored with the archive. The metadata and documentation required can vary depending on the type of data collected and the individual archive ingesting the data and general principals and common standards have been discussed previously in Documenting data creation and processing of this guide.
A detailed specification for survey metadata is outlined in the section 5 of the Geophysics guide (‘Comprehensive Documentation‘) and data creators wishing to apply this specifically to marine datasets are directed to the following sections:
- Project Metadata – project level elements that described the overall context of the dataset.
- All Survey Techniques – common elements relevant to all survey types.
- Magnetometer Surveys – specific elements relevant to marine magnetometry
- Maritime Sonar Surveys – specific elements relevant to maritime sonar surveys
- Survey Methodology – elements that describe how the survey was carried out.
- Data Treatment – a general discussion of how the software used and data processing could be included.
File level metadata, as previously highlighted, is largely dependant on the file type but a list of files that have been deposited should also be included with the archive. This should list filename, file size, software package and version used to create the file and a short description of the file’s contents. This documentation should be created in digital form to be preserved alongside the data files themselves for future users of the resource. As with file level metadata, project level metadata requirements vary and a number of standards currently exist as detailed in Documenting data creation and processing.
As discussed previously in this guide, geospatial/locational information forms an important component of any survey dataset and special attention should be paid to ensuring that such information is suitably preserved and documented in an unambiguous way. For example, for both Wessex Archaeology’s ‘Wrecks on the Seabed’ project and the VENUS project this data was seen as crucial to the project archive as it sets much of the other project data in context. It formed a vital reference point for the position of the ROV, diver or where individual photographs were taken, segments of digital video recorded or general observations made. Any processing carried out should be suitably documented.
A detailed discussion of the issues associated with spatial data can be found in Appendix 2 of the Geophysics guide (‘Georeferencing Geophysical Data).