メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((144.4437500 43.6375000, 144.4500000 43.6375000, 144.4500000 43.6416667, 144.4437500 43.6416667, 144.4437500 43.6375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral