メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.0812500 34.7958334, 138.0875000 34.7958334, 138.0875000 34.8000000, 138.0812500 34.8000000, 138.0812500 34.7958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral