メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.6062500 36.4708334, 138.6125000 36.4708334, 138.6125000 36.4750000, 138.6062500 36.4750000, 138.6062500 36.4708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral