メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.9812500 42.6791667, 139.9875000 42.6791667, 139.9875000 42.6833333, 139.9812500 42.6833333, 139.9812500 42.6791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral