メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8500000 39.8916667, 139.8562500 39.8916667, 139.8562500 39.8958334, 139.8500000 39.8958334, 139.8500000 39.8916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral