メタデータ名 polygon
<http://xmlns.oracle.com/rdf/geo/srid/4612> POLYGON((137.4625000 35.4708334, 137.4687500 35.4708334, 137.4687500 35.4750000, 137.4625000 35.4750000, 137.4625000 35.4708334)) ^^http://www.opengis.net/ont/geosparql#wktLiteral