メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.6437500 38.5958334, 139.6500000 38.5958334, 139.6500000 38.6000000, 139.6437500 38.6000000, 139.6437500 38.5958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral