メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((140.5625000 40.6708334, 140.5687500 40.6708334, 140.5687500 40.6750000, 140.5625000 40.6750000, 140.5625000 40.6708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral