メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.0687500 43.2333333, 145.0750000 43.2333333, 145.0750000 43.2375000, 145.0687500 43.2375000, 145.0687500 43.2333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral