メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.1937500 36.5708334, 137.2000000 36.5708334, 137.2000000 36.5750000, 137.1937500 36.5750000, 137.1937500 36.5708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral