メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((141.9000000 39.9458334, 141.9062500 39.9458334, 141.9062500 39.9500000, 141.9000000 39.9500000, 141.9000000 39.9458334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral