メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8625000 38.9583333, 139.8687500 38.9583333, 139.8687500 38.9625000, 139.8625000 38.9625000, 139.8625000 38.9583333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral