メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((136.5937500 36.4958334, 136.6000000 36.4958334, 136.6000000 36.5000000, 136.5937500 36.5000000, 136.5937500 36.4958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral