メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8812500 38.9708334, 139.8875000 38.9708334, 139.8875000 38.9750000, 139.8812500 38.9750000, 139.8812500 38.9708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral