メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3937500 43.3750000, 142.4000000 43.3750000, 142.4000000 43.3791667, 142.3937500 43.3791667, 142.3937500 43.3750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral