メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.7937500 40.1666667, 141.8000000 40.1666667, 141.8000000 40.1708334, 141.7937500 40.1708334, 141.7937500 40.1666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral