メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.3125000 31.6333333, 131.3187500 31.6333333, 131.3187500 31.6375000, 131.3125000 31.6375000, 131.3125000 31.6333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral