メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.8437500 36.1666667, 137.8500000 36.1666667, 137.8500000 36.1708334, 137.8437500 36.1708334, 137.8437500 36.1666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral