メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.4937500 32.0416667, 131.5000000 32.0416667, 131.5000000 32.0458334, 131.4937500 32.0458334, 131.4937500 32.0416667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral