メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.0812500 36.5041667, 138.0875000 36.5041667, 138.0875000 36.5083333, 138.0812500 36.5083333, 138.0812500 36.5041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral