メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5812500 39.1958334, 141.5875000 39.1958334, 141.5875000 39.2000000, 141.5812500 39.2000000, 141.5812500 39.1958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral