メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.751674439793 43.1989440123683, 141.751026503724 43.1995892654575, 141.750404383245 43.1989241324899, 141.751298710049 43.1979114363429, 141.751551847184 43.1980375822543, 141.752213530363 43.1983830983941, 141.751674439793 43.1989440123683)) ^^http://www.opengis.net/ont/geosparql#wktLiteral