メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.3500000 36.8458334, 138.3562500 36.8458334, 138.3562500 36.8500000, 138.3500000 36.8500000, 138.3500000 36.8458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral