メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.1750000 36.3958334, 137.1812500 36.3958334, 137.1812500 36.4000000, 137.1750000 36.4000000, 137.1750000 36.3958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral