メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8062500 37.4958334, 139.8125000 37.4958334, 139.8125000 37.5000000, 139.8062500 37.5000000, 139.8062500 37.4958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral