メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.1375000 43.2250000, 145.1437500 43.2250000, 145.1437500 43.2291667, 145.1375000 43.2291667, 145.1375000 43.2250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral