メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.908078227808 43.484827417188, 141.907161751709 43.4849749022957, 141.90707701241 43.4846764730178, 141.906784862221 43.48371876445, 141.907694582192 43.4835802639786, 141.908078227808 43.484827417188)) ^^http://www.opengis.net/ont/geosparql#wktLiteral