メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.3687500 43.7666667, 142.3750000 43.7666667, 142.3750000 43.7708334, 142.3687500 43.7708334, 142.3687500 43.7666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral