メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9312500 39.8958334, 141.9375000 39.8958334, 141.9375000 39.9000000, 141.9312500 39.9000000, 141.9312500 39.8958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral