メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.0750000 39.9500000, 141.0812500 39.9500000, 141.0812500 39.9541667, 141.0750000 39.9541667, 141.0750000 39.9500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral