メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3062500 44.5750000, 142.3125000 44.5750000, 142.3125000 44.5791667, 142.3062500 44.5791667, 142.3062500 44.5750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral