メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.4500000 43.0166667, 141.4562500 43.0166667, 141.4562500 43.0208334, 141.4500000 43.0208334, 141.4500000 43.0166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral