メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.1375000 42.4333333, 141.1437500 42.4333333, 141.1437500 42.4375000, 141.1375000 42.4375000, 141.1375000 42.4333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral