メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.7937500 42.2791667, 139.8000000 42.2791667, 139.8000000 42.2833333, 139.7937500 42.2833333, 139.7937500 42.2791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral