メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5500000 43.1500000, 141.5562500 43.1500000, 141.5562500 43.1541667, 141.5500000 43.1541667, 141.5500000 43.1500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral