メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8062500 40.0666667, 141.8125000 40.0666667, 141.8125000 40.0708334, 141.8062500 40.0708334, 141.8062500 40.0666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral