メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.5875000 42.2916667, 142.5937500 42.2916667, 142.5937500 42.2958334, 142.5875000 42.2958334, 142.5875000 42.2916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral