メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.6375000 36.5458334, 138.6437500 36.5458334, 138.6437500 36.5500000, 138.6375000 36.5500000, 138.6375000 36.5458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral