メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.6812500 32.4958334, 131.6875000 32.4958334, 131.6875000 32.5000000, 131.6812500 32.5000000, 131.6812500 32.4958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral