メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.9375000 35.2250000, 138.9437500 35.2250000, 138.9437500 35.2291667, 138.9375000 35.2291667, 138.9375000 35.2250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral