メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((144.5625000 43.3791667, 144.5687500 43.3791667, 144.5687500 43.3833333, 144.5625000 43.3833333, 144.5625000 43.3791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral