メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.4625000 32.0166667, 131.4687500 32.0166667, 131.4687500 32.0208334, 131.4625000 32.0208334, 131.4625000 32.0166667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral