メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8687500 39.9958334, 141.8750000 39.9958334, 141.8750000 40.0000000, 141.8687500 40.0000000, 141.8687500 39.9958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral