メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.2187500 43.4750000, 142.2250000 43.4750000, 142.2250000 43.4791667, 142.2187500 43.4791667, 142.2187500 43.4750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral