メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.0812500 31.7041667, 131.0875000 31.7041667, 131.0875000 31.7083333, 131.0812500 31.7083333, 131.0812500 31.7041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral