メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.1812500 32.1791667, 131.1875000 32.1791667, 131.1875000 32.1833333, 131.1812500 32.1833333, 131.1812500 32.1791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral