メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.6750000 43.5333333, 143.6812500 43.5333333, 143.6812500 43.5375000, 143.6750000 43.5375000, 143.6750000 43.5333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral