メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.3375000 42.5416667, 141.3437500 42.5416667, 141.3437500 42.5458334, 141.3375000 42.5458334, 141.3375000 42.5416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral