メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.9937500 36.6708334, 138.0000000 36.6708334, 138.0000000 36.6750000, 137.9937500 36.6750000, 137.9937500 36.6708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral