メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.0375000 37.8375000, 139.0437500 37.8375000, 139.0437500 37.8416667, 139.0375000 37.8416667, 139.0375000 37.8375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral