メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.5187500 38.0708334, 139.5250000 38.0708334, 139.5250000 38.0750000, 139.5187500 38.0750000, 139.5187500 38.0708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral