メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.1500000 43.5375000, 142.1562500 43.5375000, 142.1562500 43.5416667, 142.1500000 43.5416667, 142.1500000 43.5375000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral