メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.0750000 36.0250000, 138.0812500 36.0250000, 138.0812500 36.0291667, 138.0750000 36.0291667, 138.0750000 36.0250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral