メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((145.2187500 43.5666667, 145.2250000 43.5666667, 145.2250000 43.5708334, 145.2187500 43.5708334, 145.2187500 43.5666667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral