メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.7000000 35.3000000, 138.7062500 35.3000000, 138.7062500 35.3041667, 138.7000000 35.3041667, 138.7000000 35.3000000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral