メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.4937500 33.3750000, 131.5000000 33.3750000, 131.5000000 33.3791667, 131.4937500 33.3791667, 131.4937500 33.3750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral