メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.403687875787 44.1782703065046, 142.402472046963 44.1780803883639, 142.40273986857 44.1775148827341, 142.403868555913 44.1776994303523, 142.403687875787 44.1782703065046)) ^^http://www.opengis.net/ont/geosparql#wktLiteral