メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.6750000 42.2041667, 142.6812500 42.2041667, 142.6812500 42.2083333, 142.6750000 42.2083333, 142.6750000 42.2041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral