メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9812500 35.0500000, 138.9875000 35.0500000, 138.9875000 35.0541667, 138.9812500 35.0541667, 138.9812500 35.0500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral