メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.8000000 42.5666667, 140.8062500 42.5666667, 140.8062500 42.5708334, 140.8000000 42.5708334, 140.8000000 42.5666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral