メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0500000 45.3083333, 142.0562500 45.3083333, 142.0562500 45.3125000, 142.0500000 45.3125000, 142.0500000 45.3083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral