メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((131.8437500 32.6958334, 131.8500000 32.6958334, 131.8500000 32.7000000, 131.8437500 32.7000000, 131.8437500 32.6958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral