メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.2750000 38.6916667, 140.2812500 38.6916667, 140.2812500 38.6958334, 140.2750000 38.6958334, 140.2750000 38.6916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral