メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.4375000 38.5916667, 140.4437500 38.5916667, 140.4437500 38.5958334, 140.4375000 38.5958334, 140.4375000 38.5916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral