メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.0312500 37.8958334, 139.0375000 37.8958334, 139.0375000 37.9000000, 139.0312500 37.9000000, 139.0312500 37.8958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral