メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.405578277127 43.8315425625009, 142.403919727998 43.8303409853893, 142.406333440064 43.8285708785724, 142.40716058369 43.8291776404291, 142.407995627109 43.8297482774089, 142.406923713184 43.8305379907521, 142.405578277127 43.8315425625009)) ^^http://www.opengis.net/ont/geosparql#wktLiteral