メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.7250000 42.6333333, 141.7312500 42.6333333, 141.7312500 42.6375000, 141.7250000 42.6375000, 141.7250000 42.6333333)) ^^http://www.opengis.net/ont/geosparql#wktLiteral