メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.9000000 42.6750000, 139.9062500 42.6750000, 139.9062500 42.6791667, 139.9000000 42.6791667, 139.9000000 42.6750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral