メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.7937500 42.2541667, 139.8000000 42.2541667, 139.8000000 42.2583333, 139.7937500 42.2583333, 139.7937500 42.2541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral