メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.0125000 43.4291667, 145.0187500 43.4291667, 145.0187500 43.4333333, 145.0125000 43.4333333, 145.0125000 43.4291667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral