メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.1875000 34.6500000, 138.1937500 34.6500000, 138.1937500 34.6541667, 138.1875000 34.6541667, 138.1875000 34.6500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral