メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.3812500 38.0916667, 139.3875000 38.0916667, 139.3875000 38.0958334, 139.3812500 38.0958334, 139.3812500 38.0916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral