メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.6437500 45.3333333, 141.6500000 45.3333333, 141.6500000 45.3375000, 141.6437500 45.3375000, 141.6437500 45.3333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral