メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0625000 43.5333333, 142.0687500 43.5333333, 142.0687500 43.5375000, 142.0625000 43.5375000, 142.0625000 43.5333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral