メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5750000 37.4000000, 138.5812500 37.4000000, 138.5812500 37.4041667, 138.5750000 37.4041667, 138.5750000 37.4000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral