メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.0437500 34.6833333, 138.0500000 34.6833333, 138.0500000 34.6875000, 138.0437500 34.6875000, 138.0437500 34.6833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral