メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.6125000 43.1333333, 141.6187500 43.1333333, 141.6187500 43.1375000, 141.6125000 43.1375000, 141.6125000 43.1333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral