メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.6500000 41.8916667, 140.6562500 41.8916667, 140.6562500 41.8958334, 140.6500000 41.8958334, 140.6500000 41.8916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral