メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.903208840723 43.4977060229481, 141.901716122565 43.4979479146991, 141.901682013401 43.4978489673641, 141.901337266568 43.4969669083097, 141.901261928237 43.4968103448647, 141.902863955627 43.4965377746435, 141.903208840723 43.4977060229481)) ^^http://www.opengis.net/ont/geosparql#wktLiteral