メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.1875000 42.9791667, 143.1937500 42.9791667, 143.1937500 42.9833333, 143.1875000 42.9833333, 143.1875000 42.9791667)) ^^http://www.opengis.net/ont/geosparql#wktLiteral