メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.2937500 36.8083333, 138.3000000 36.8083333, 138.3000000 36.8125000, 138.2937500 36.8125000, 138.2937500 36.8083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral