メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0375000 39.1875000, 141.0437500 39.1875000, 141.0437500 39.1916667, 141.0375000 39.1916667, 141.0375000 39.1875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral