メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.4312500 43.2750000, 145.4375000 43.2750000, 145.4375000 43.2791667, 145.4312500 43.2791667, 145.4312500 43.2750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral