メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.0500000 43.0375000, 145.0562500 43.0375000, 145.0562500 43.0416667, 145.0500000 43.0416667, 145.0500000 43.0375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral