メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8875000 42.4791667, 140.8937500 42.4791667, 140.8937500 42.4833333, 140.8875000 42.4833333, 140.8875000 42.4791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral