メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.0875000 34.7125000, 138.0937500 34.7125000, 138.0937500 34.7166667, 138.0875000 34.7166667, 138.0875000 34.7125000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral