メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5062500 42.9333333, 141.5125000 42.9333333, 141.5125000 42.9375000, 141.5062500 42.9375000, 141.5062500 42.9333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral