メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.0062500 36.8916667, 137.0125000 36.8916667, 137.0125000 36.8958334, 137.0062500 36.8958334, 137.0062500 36.8916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral