メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.0187500 37.8708334, 139.0250000 37.8708334, 139.0250000 37.8750000, 139.0187500 37.8750000, 139.0187500 37.8708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral