メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3312500 44.5458334, 142.3375000 44.5458334, 142.3375000 44.5500000, 142.3312500 44.5500000, 142.3312500 44.5458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral