メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((138.2750000 34.8875000, 138.2812500 34.8875000, 138.2812500 34.8916667, 138.2750000 34.8916667, 138.2750000 34.8875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral