メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.912829958028 43.4863243741974, 141.911630285401 43.4855440387319, 141.911856899328 43.4855094774168, 141.912520559988 43.4854064791809, 141.912699068839 43.4860977119616, 141.912724413709 43.4861728601033, 141.912829958028 43.4863243741974)) ^^http://www.opengis.net/ont/geosparql#wktLiteral