メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.3500000 31.9791667, 131.3562500 31.9791667, 131.3562500 31.9833333, 131.3500000 31.9833333, 131.3500000 31.9791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral