メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0250000 43.4500000, 142.0312500 43.4500000, 142.0312500 43.4541667, 142.0250000 43.4541667, 142.0250000 43.4500000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral