メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.762339477703 43.1870539297436, 141.762793572937 43.1872873150509, 141.762370439242 43.1877296316505, 141.761872815638 43.1882442072352, 141.761414740675 43.1880091144197, 141.760947111723 43.1877735566297, 141.761423272252 43.1872574160138, 141.761856786391 43.1868093795531, 141.762339477703 43.1870539297436)) ^^http://www.opengis.net/ont/geosparql#wktLiteral