メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8375000 36.6708334, 137.8437500 36.6708334, 137.8437500 36.6750000, 137.8375000 36.6750000, 137.8375000 36.6708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral