メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.1625000 37.7166667, 139.1687500 37.7166667, 139.1687500 37.7208334, 139.1625000 37.7208334, 139.1625000 37.7166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral