メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.8812500 37.2875000, 138.8875000 37.2875000, 138.8875000 37.2916667, 138.8812500 37.2916667, 138.8812500 37.2875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral