メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8625000 43.1875000, 140.8687500 43.1875000, 140.8687500 43.1916667, 140.8625000 43.1916667, 140.8625000 43.1875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral