メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.894878542461 43.0092262377776, 142.894376465557 43.0096652472046, 142.894677572122 43.0098392397367, 142.894121263524 43.0099129068485, 142.89365945265 43.0084780951844, 142.894878542461 43.0092262377776)) ^^http://www.opengis.net/ont/geosparql#wktLiteral