メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.7312500 37.1166667, 138.7375000 37.1166667, 138.7375000 37.1208334, 138.7312500 37.1208334, 138.7312500 37.1166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral