メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.329273817271 43.7698813585795, 142.328448245985 43.7696339057907, 142.328786224942 43.7690898757102, 142.329138076608 43.7684808591579, 142.329916240955 43.7687210959482, 142.329273817271 43.7698813585795)) ^^http://www.opengis.net/ont/geosparql#wktLiteral