メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.403398954202 44.1792520963337, 142.402008431048 44.1790437925602, 142.402137362919 44.1787870898471, 142.402472046963 44.1780803883639, 142.403687875787 44.1782703065046, 142.403398954202 44.1792520963337)) ^^http://www.opengis.net/ont/geosparql#wktLiteral