メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.4125000 42.1750000, 140.4187500 42.1750000, 140.4187500 42.1791667, 140.4125000 42.1791667, 140.4125000 42.1750000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral