メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.3250000 36.8333333, 138.3312500 36.8333333, 138.3312500 36.8375000, 138.3250000 36.8375000, 138.3250000 36.8333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral