メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.1437500 42.9958334, 143.1500000 42.9958334, 143.1500000 43.0000000, 143.1437500 43.0000000, 143.1437500 42.9958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral