メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.2187500 37.8916667, 139.2250000 37.8916667, 139.2250000 37.8958334, 139.2187500 37.8958334, 139.2187500 37.8916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral