メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.9312500 42.3958334, 140.9375000 42.3958334, 140.9375000 42.4000000, 140.9312500 42.4000000, 140.9312500 42.3958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral