メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.1500000 42.7750000, 140.1562500 42.7750000, 140.1562500 42.7791667, 140.1500000 42.7791667, 140.1500000 42.7750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral