メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9875000 37.3541667, 138.9937500 37.3541667, 138.9937500 37.3583333, 138.9875000 37.3583333, 138.9875000 37.3541667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral