メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9875000 34.9875000, 138.9937500 34.9875000, 138.9937500 34.9916667, 138.9875000 34.9916667, 138.9875000 34.9875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral