メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.2500000 37.1666667, 138.2562500 37.1666667, 138.2562500 37.1708334, 138.2500000 37.1708334, 138.2500000 37.1666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral