メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8062500 38.1458334, 140.8125000 38.1458334, 140.8125000 38.1500000, 140.8062500 38.1500000, 140.8062500 38.1458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral