メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.9625000 43.2166667, 140.9687500 43.2166667, 140.9687500 43.2208334, 140.9625000 43.2208334, 140.9625000 43.2166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral