メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((142.0875000 43.9250000, 142.0937500 43.9250000, 142.0937500 43.9291667, 142.0875000 43.9291667, 142.0875000 43.9250000)) ^^http://www.opengis.net/ont/geosparql#wktLiteral