メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4375000 36.6916667, 137.4437500 36.6916667, 137.4437500 36.6958334, 137.4375000 36.6958334, 137.4375000 36.6916667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral