メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.2312500 42.5458334, 141.2375000 42.5458334, 141.2375000 42.5500000, 141.2312500 42.5500000, 141.2312500 42.5458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral