メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.6375000 43.0666667, 141.6437500 43.0666667, 141.6437500 43.0708334, 141.6375000 43.0708334, 141.6375000 43.0666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral