メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8875000 38.1916667, 140.8937500 38.1916667, 140.8937500 38.1958334, 140.8875000 38.1958334, 140.8875000 38.1916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral