メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0312500 38.4708334, 141.0375000 38.4708334, 141.0375000 38.4750000, 141.0312500 38.4750000, 141.0312500 38.4708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral