メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.1000000 36.4916667, 138.1062500 36.4916667, 138.1062500 36.4958334, 138.1000000 36.4958334, 138.1000000 36.4916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral