メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.4687500 40.6958334, 140.4750000 40.6958334, 140.4750000 40.7000000, 140.4687500 40.7000000, 140.4687500 40.6958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral