メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.6875000 40.5708334, 140.6937500 40.5708334, 140.6937500 40.5750000, 140.6875000 40.5750000, 140.6875000 40.5708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral