メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8937500 35.2958334, 139.9000000 35.2958334, 139.9000000 35.3000000, 139.8937500 35.3000000, 139.8937500 35.2958334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral