メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.0437500 34.7958334, 139.0500000 34.7958334, 139.0500000 34.8000000, 139.0437500 34.8000000, 139.0437500 34.7958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral