メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.1375000 31.7666667, 131.1437500 31.7666667, 131.1437500 31.7708334, 131.1375000 31.7708334, 131.1375000 31.7666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral