GeoBlacklight Metadata

What is GeoBlacklight Metadata

JHU's metadata profile is based on the GeoBlacklight (GBL) Metadata Schema Version 1.0, which was made to help standardize metadata across GeoBlacklight instances. A “metadata schema for GIS resource discovery” based on Dublin Core, the GBL schema focuses on descriptive elements meant to aid user discovery rather than technical metadata. JHU-GMAP shares this descriptive focus. JHU-GMAP also draws from the Big Ten Academic Alliance Geospatial Data Project’s Metadata Profile (version 3.1), which is also based on the GBL schema.

Under the GBL schema, metadata is encoded and submitted to GeoBlacklight instances as JSON files. While our metadata will also be submitted as JSON files, this guide is more focused on how to properly understand and transcribe individual elements than how to encode them in JSON. More information on transforming this metadata from a CSV to a JSON file can be found: here.

For those familiar with the GBL schema, there are some key differences between the GBL schema and JHU-GMAP that may be useful to note.

• The GBL schema requires the use of only 6 elements; JHU-GMAP requires a total of 14 elements (the 6 required by GBL and 8 additional elements). Therefore, metadata created under JHU-GMAP requirements always will fulfill GBL schema requirements, but the reverse is not necessarily true.

• For the elements of Creator, Publisher, Subjects, and Spatial Coverage, JHU-GMAP requires the use of selected controlled vocabularies or adherence to specific formatting rules. The GBL schema recommends but does not require controlled vocabularies for these elements.

A note on examples:

In the examples in this guide, the examples are shown how they would be entered in a spreadsheet for subsequent conversion to JSON through a script. This means that elements with multiple values are shown with each value separated by a pipe, which will later be converted into an array value in JSON. For instance, see the following Spatial Coverage element with multiple values as entered in a spreadsheet and as seen in the final JSON document.

Element and values in spreadsheet:

Spatial Coverage
District 9, Franklin, Maryland, United States|Hampstead, Maryland, United States|New Windsor, Maryland, United States|Winfield, Maryland, United States

Element and values in JSON file:

"dct_spatial_sm": [
    "District 9, Franklin, Maryland, United States",
    "Hampstead, Maryland, United States",
    "New Windsor, Maryland, United States",
    "Winfield, Maryland, United States"
  ]

Some examples in JHU-GMAP are drawn from items in the Big Ten Academic Alliance Geoportal.