メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5500000 35.1916667, 138.5562500 35.1916667, 138.5562500 35.1958334, 138.5500000 35.1958334, 138.5500000 35.1916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral