メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.3312500 37.8791667, 138.3375000 37.8791667, 138.3375000 37.8833333, 138.3312500 37.8833333, 138.3312500 37.8791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral