メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.8750000 42.1833333, 142.8812500 42.1833333, 142.8812500 42.1875000, 142.8750000 42.1875000, 142.8750000 42.1833333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral