メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.7750000 37.6541667, 138.7812500 37.6541667, 138.7812500 37.6583333, 138.7750000 37.6583333, 138.7750000 37.6541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral