メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((144.2187500 44.0875000, 144.2250000 44.0875000, 144.2250000 44.0916667, 144.2187500 44.0916667, 144.2187500 44.0875000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral