メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((139.8937500 38.9458334, 139.9000000 38.9458334, 139.9000000 38.9500000, 139.8937500 38.9500000, 139.8937500 38.9458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral