メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.4437500 31.8250000, 131.4500000 31.8250000, 131.4500000 31.8291667, 131.4437500 31.8291667, 131.4437500 31.8250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral