メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.911819032819 43.4829370529865, 141.911040736316 43.4830522975955, 141.910702537759 43.4818013060413, 141.911448637273 43.4816591730097, 141.91159498863 43.4821640822881, 141.911674738298 43.4824391827722, 141.911819032819 43.4829370529865)) ^^http://www.opengis.net/ont/geosparql#wktLiteral