メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.5437500 43.7708334, 141.5500000 43.7708334, 141.5500000 43.7750000, 141.5437500 43.7750000, 141.5437500 43.7708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral