メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.5375000 35.4333333, 138.5437500 35.4333333, 138.5437500 35.4375000, 138.5375000 35.4375000, 138.5375000 35.4333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral