メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((143.0625000 42.9333333, 143.0687500 42.9333333, 143.0687500 42.9375000, 143.0625000 42.9375000, 143.0625000 42.9333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral