メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0375000 38.7333333, 141.0437500 38.7333333, 141.0437500 38.7375000, 141.0375000 38.7375000, 141.0375000 38.7333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral