メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9937500 34.7416667, 139.0000000 34.7416667, 139.0000000 34.7458334, 138.9937500 34.7458334, 138.9937500 34.7416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral