メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2375000 38.4958334, 141.2437500 38.4958334, 141.2437500 38.5000000, 141.2375000 38.5000000, 141.2375000 38.4958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral