メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.8437500 39.4083333, 141.8500000 39.4083333, 141.8500000 39.4125000, 141.8437500 39.4125000, 141.8437500 39.4083333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral