メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.2750000 43.2916667, 145.2812500 43.2916667, 145.2812500 43.2958334, 145.2750000 43.2958334, 145.2750000 43.2916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral