メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9750000 43.0625000, 141.9812500 43.0625000, 141.9812500 43.0666667, 141.9750000 43.0666667, 141.9750000 43.0625000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral