メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9375000 37.5583333, 138.9437500 37.5583333, 138.9437500 37.5625000, 138.9375000 37.5625000, 138.9375000 37.5583333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral