メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.4687500 32.0458334, 131.4750000 32.0458334, 131.4750000 32.0500000, 131.4687500 32.0500000, 131.4687500 32.0458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral