メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5250000 42.9666667, 141.5312500 42.9666667, 141.5312500 42.9708334, 141.5250000 42.9708334, 141.5250000 42.9666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral