メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.1875000 44.0166667, 145.1937500 44.0166667, 145.1937500 44.0208334, 145.1875000 44.0208334, 145.1875000 44.0166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral