メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.8062500 33.0666667, 131.8125000 33.0666667, 131.8125000 33.0708334, 131.8062500 33.0708334, 131.8062500 33.0666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral