メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.6375000 44.3041667, 142.6437500 44.3041667, 142.6437500 44.3083333, 142.6375000 44.3083333, 142.6375000 44.3041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral