メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.4125000 43.4041667, 142.4187500 43.4041667, 142.4187500 43.4083333, 142.4125000 43.4083333, 142.4125000 43.4041667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral