メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8437500 38.0208334, 140.8500000 38.0208334, 140.8500000 38.0250000, 140.8437500 38.0250000, 140.8437500 38.0208334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral