メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.5687500 36.9083333, 137.5750000 36.9083333, 137.5750000 36.9125000, 137.5687500 36.9125000, 137.5687500 36.9083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral