メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0437500 42.5833333, 142.0500000 42.5833333, 142.0500000 42.5875000, 142.0437500 42.5875000, 142.0437500 42.5833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral