メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.2187500 43.3041667, 145.2250000 43.3041667, 145.2250000 43.3083333, 145.2187500 43.3083333, 145.2187500 43.3041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral