メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.4750000 43.3708334, 140.4812500 43.3708334, 140.4812500 43.3750000, 140.4750000 43.3750000, 140.4750000 43.3708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral